List of
peer-reviewed publications
1) Baicheva, T., Topalova, S., On the
diffusion of the Improved Generalized Feistel. Advances in Mathematics
of Communications, 16, 1, American Institute of Mathematical Sciences, 2022,
95-114.
2)
Betten, A.,
Topalova, S., Zhelezova, S., Parallelisms
of PG(3,4) invariant under an elementary abelian group of order 4.
Applicable Algebra in Engineering, Communication and Computing, 33, 6,
Springer, 2022, 649-674.
3) Topalova, S., Zhelezova S., Backtrack
search for parallelisms of projective spaces. In: Flocchini P., Moura
L. (eds) Combinatorial Algorithms. IWOCA 2021. LNCS, 12757, Springer, 2021,
544-557.
4) Topalova, S., Zhelezova S., New
Parallelisms of PG(3,5) with Automorphisms of Order 8. In: Boulier F.,
England M., Sadykov T.M., Vorozhtsov E.V. (eds) Computer Algebra in Scientific
Computing. CASC 2021. LNCS, 12865, Springer, Cham, 2021, 409-419.
5) Topalova, S., Zhelezova S., On parallelisms of
PG(5,2) invariant under a cyclic subgroup of order 21. XVII
International Symposium Problems of Redundancy in Information and Control
Systems, IEEExplore, 2021, 97-100.
6) Topalova, S., Zhelezova S., Parallelisms
of PG(3,5) with an automorphism group of order 25. In:
Nešetřil J., Perarnau G., Rué J., Serra O. (eds) Extended
Abstracts EuroComb 2021. Trends in Mathematics, 14, Springer Birkhäuser,
Cham., 2021, 668-674.
7) Topalova, S., Zhelezova S., Some parallelisms of
PG(3,5) involving a definite type of spread. 2020 Algebraic and
Combinatorial Coding Theory, IEEExplore, 2021, 135-139.
8) Topalova, S., Zhelezova, S., Isomorphism
and Invariants of Parallelisms of Projective Spaces. Lecture Notes in
Computer Science, 12097, Springer, Cham, 2020,
162-172.
9) Betten, A., Topalova, S., Zhelezova, S., New
Uniform Subregular Parallelisms of PG(3,4) Invariant Under an Automorphism of
Order 2. Cybernetics and Information Technologies, 20, 6, Institute of
Information and Communication Technologies - BAS, 2020, 18-27.
10)
Baicheva, T.,
Topalova S., On the diffusion property of the Improved Generalized
Feistel with different permutations for
each round, In: Ćirić M., Droste M., Pin JÉ. (eds),
Algebraic Informatics, CAI 2019, Lecture Notes in Computer Science, 11545,
Springer, 2019, 38-49.
11)
Betten, A.,
Topalova S., Zhelezova S., Parallelisms
of PG(3,4) invariant under cyclic groups of order 4, In:
Ćirić M., Droste M., Pin JÉ. (eds) Algebraic Informatics, CAI
2019, Lecture Notes in Computer Science, 11545, Springer, Cham, 2019, 88-99.
12)
Baicheva T.,
Topalova S., Classification
of optimal (v, k, 1) binary cyclically permutable constant weight codes with
k=5, 6 and 7 and small lengths, Designs
Codes and Cryptography 87 (2 – 3)
(2019), 1573-7586.
13)
Topalova S.,
Zhelezova S., Types of spreads
and duality of the parallelisms of PG(3,5) with automorphisms of order 13,
Designs, Codes and Cryptography 87 (2
– 3) (2019), 495-507.
14)
Baicheva T.,
Topalova S., Classification
of strongly conflict-avoiding codes,
IEEE Communications Letters 22 (12) (2018),
2415-2418.
15)
Betten A.,
Topalova S., Zhelezova S., Parallelisms
of PG(3, 4) invariant under a Baer involution, Proceedings of the 16th
International Workshop on Algebraic and Combinatorial Coding Theory,
Svetlogorsk, Russia, 2018, 57-61.
16)
Baicheva, T.,
Topalova S., On
Tight Optimal Conflict-avoiding Codes for 3, 4, 5 and 6 Active Users, Cybernetics and Information Technologies
18 (5) (2018), 5-11.
17)
Baicheva T.,
Topalova S., Classification
of optimal conflict-avoiding codes of weights 6 and 7, Electronic Notes in Discrete Mathematics
57 (2017), 9 – 14.
18)
Baicheva T.,
Topalova S., Optimal
conflict-avoiding codes for 3, 4 and 5 active users, Problems of Information Transmission 53 (1) (2017), 42 - 50.
19)
S. Topalova, S.
Zhelezova, New
parallelisms of PG(3, 4), Electronic Notes in Discrete Mathematics
57 (2017), 193 - 198.
20)
Topalova S.,
Zhelezova S., New regular
parallelisms of PG(3,5), Journal
of Combinatorial Designs 24 (10) (2016), 473 - 482..
21)
Topalova S., On
the resolutions of cyclic Steiner triple systems with small parameters,
Journal of Algebra Combinatorics Discrete
Structures and Applications 3 (3) (2016), 201 - 208.
22)
Topalova S., Conjugates for finding the automorphism group and
isomorphism of design resolutions, Serdica
Journal of Computing 10 (1) (2016), 79 – 92.
23)
T. Baicheva and
S. Topalova, Construction and classification of optimal (v,5,3,1) optical orthogonal
codes, International
Scientific Journal Science. Business. Society 5 (2016), 7 - 8.
24)
S. Topalova, S.
Zhelezova, On
point-transitive and transitive deficiency one parallelisms of PG(3,4), Designs Codes and Cryptography 75(1) (2015), 9-19.
25)
Baicheva T.,
Topalova S., Maximal (v,4,3,1) optical orthogonal codes for asynchronous
transmission. In Proc. Scientitfic Jubilee Conference 25 Years Faculty of
Mathematics and Informatics, Veliko Tarnovo, Bulgaria (2015), 80--85.
26)
T. Baicheva, S.
Topalova, Classification
of maximal optical orthogonal codes of weight 3 and small lengths, Serdica Journal of Computing 9(1)
(2015), 83 – 92.
27)
S. Topalova, S.
Zhelezova, Doubly resolvable designs with small parameters, Ars Combinatoria 117
(October) (2014), 289-302.
28)
R. Shaw, S.
Topalova, Book
spreads in PG (7, 2), Discrete Mathematics 330 (2014), 76-86.
29)
T. Baicheva, S.
Topalova, New perfect difference
families, Fourteenth International Workshop on Algebraic and
Combinatorial Coding Theory, September 7–13, 2014, Svetlogorsk (Kaliningrad
region), Russia, 18–23.
30)
McDonough T.P.,
Shaw R., Topalova S., Classification
of book spreads in PG(5,2), Note Di Matematica, 33(2) (2013), 43-64.
31)
Topalova S.,
Zhelezova S., Orthogonal
resolutions and latin squares, Serdica
Journal of Computing 7(1) (2013), 13 - 24.
32)
Topalova S.,
Zhelezova S., On
transitive parallelisms of PG(3,4), Applicable
Algebra in Engineering, Communication and Computing 24 (3-4) (2013), 159 -
164.
33)
Baicheva T.,
Topalova S., Optimal
(v,5,2,1) optical orthogonal codes of small v, Applicable Algebra in Engineering, Communication and Computing 24
(3-4) (2013), 165 - 177.
34)
S. Topalova, S.
Zhelezova, Parallelisms
of PG(3,5) with automorphisms of order 13, Proceedings of the Seventh
International Workshop on Optimal Codes and Related Topics, Albena, Bulgaria (2013), 176 – 180.
35)
Baicheva T.,
Topalova S., Classification
results for (v, k, 1) cyclic difference families with small parameters,
Mathematics of Distances and Applications,
M. Deza, M. Petitjean, K. Markov eds., in International book series: Information Science and Computing, book
25 (2012), 24 – 30.
36)
T. Baicheva, S. Topalova, Optimal (v, 3, 1)
binary cyclically permutable constant weight codes with small v, Proc.
of the International Workshop on Algebraic and Combinatorial Coding Theory,
Pomorie, Bulgaria, pp. 41 -- 46, 2012.
37)
R. Shaw, S.Topalova, On the types of
book spreads of PG(7,2), Proc. of the International Workshop on
Algebraic and Combinatorial Coding Theory, Pomorie, Bulgaria, pp. 293 - 298,
2012.
38)
S. Topalova, S.
Zhelezova, Parallelisms
of PG(3,4) with automorphisms of order 5, Proc. of the International
Workshop on Algebraic and Combinatorial Coding Theory, Pomorie, Bulgaria, pp.
311- 316, 2012.
39)
T. Baicheva, S.
Topalova, Classification
results for (v, k, 1) cyclic difference families with small parameters,
Abstracts of ITHEA International Conference "Mathematics of Distances and
Applications" (
40)
T. Baicheva, S.
Topalova, Optimal
(v, 4, 2, 1) optical orthogonal codes with small parameters , Journal of Combinatorial Designs 20 (2)
(2012), 142-160.
41)
T. Baicheva, S.
Topalova, Classification
of optimal (v,4,1) binary cyclically permutable constant-weight codes and
cyclic 2-(v,4,1) designs with v£76, Problems of Information Transmission
47(3) (2011), 224–231.
42)
T. Baicheva and
S. Topalova, Optimal (v, 5, 2, 1) optical
orthogonal codes with v≤104,
Proc. of Annual Workshop on Coding
Theory and Applications, Gabrovo, Bulgaria (2011), 11-14.
43)
T. Baicheva and
S. Topalova, Classification of optical
orthogonal codes and spreads by backtrack search on a parallel computer,
Proc. of Annual Workshop on Coding Theory
and Applications, Gabrovo, Bulgaria (2011), 7-10.
44)
S. Topalova, S.
Zhelezova, 2-spreads
and transitive and orthogonal 2-parallelisms of PG(5,2), Graphs and
Combinatorics, 26(5) (2010), 727
- 735.
45)
T. Baicheva and
S. Topalova, An
algorithm for classification of optimal optical orthogonal codes ,
Proc. of Annual Workshop Coding Theory
and Applications, Veliko Tarnovo, Bulgaria (2010) 11-14.
46)
T. Baicheva and
S. Topalova, Classification
of optimal (v,4,1) optical orthogonal codes with v<=76, Proc. of the
International Workshop on Algebraic and
Combinatorial Coding Theory,
47)
S. Topalova, S.
Zhelezova, Parallelisms of PG(3,4) with automorphisms of
order 7, Proceedings of the
Sixth International Workshop on Optimal Codes and Related Topics, Varna, June 2009, Bulgaria, 184-188.
48)
Z. Mateva, S.
Topalova, Hadamard
2-(63,31,15) designs invariant under the dihedral group of order 10, Discrete
Mathematics, Volume 309, Issue 6 (2009), 1347-1356.
49)
Z. Mateva, S. Topalova,
Line
spreads of PG(5,2), Journal of
Combinatorial Designs 17(1)
(2009), 90-102.
50)
S.Topalova,
S.Zhelezova, Classification
of doubly resolvable designs and orthogonal resolutions, Enhancing
Cryptographic Primitives with Techniques from Error Correcting codes, B.Preneel,
S.Dodunekov, V. Rijmen, S. Nikova eds.,
in NATO Science for Peace and Security Series - D: Information and
Communication Security, Volume 23, IOS
Press, Amsterdam (2009), 260 - 264.
51)
S. Topalova, S.
Zhelezova, Sets of mutually orthogonal resolutions of
BIBDs, Proceedings of the Eleventh International Workshop on Algebraic and Combinatorial Coding Theory,
Pamporovo, Bulgaria (2008), 280-285.
52)
S. Topalova, S.
Zhelezova, Classification of the
2-spreads of PG(5,2), Mathematics and
Education in Mathematics (2008), 163-169.
53)
Kaski P.,
Östergård P., Topalova S., Zlatarski R., Steiner Triple Systems of Order 19 and 21 with
Subsystems of Order 7, Discrete Mathematics 308 (2008),
2732-2741.
54)
Z. Mateva, S.
Topalova, Doubles of Hadamard 2-(19,9,4) Designs with Automorphisms of Order 3,
Proceedings of the Fifth International
Workshop on Optimal Codes and Related Topics, Balchik, June 2007,
Bulgaria, 183-189.
55)
S. Topalova,
56)
Z. Mateva,
57)
V. Fack, S.
Topalova, J. Winne, R. Zlatarski, Enumeration
of the doubles of the projective plane of order 4, Discrete
Mathematics 306 (2006) 2141-2151.
58)
Z. Mateva,
59)
S. Topalova, S.
Zhelezova, On the structure of doubly resolvable 2-(21,3,1) designs, Proceedings of the Tenth International
Workshop on Algebraic and Combinatorial Coding Theory,
Zvenigorod, Russia (2006), 263-268.
60)
S. Topalova, S.
Zhelezova, On the classification of doubly resolvable designs, Proceedings of the Fourth International
Workshop on Optimal Codes and Related Topics, Pamporovo, June
2005,
61)
V. Fack, S.
Topalova, J. Winne, Enumeration of the reducible 2-(21,5,2) designs, Proceedings
of the Fourth International Workshop on Optimal Codes and Related
Topics , Pamporovo, Bulgaria (2005), 146-151.
62)
V. Fack,
63)
Topalova S.,
STS(21) with Automorphisms of order 3 with 3 fixed points and 7 fixed blocks, Mathematica
Balkanica 18 (1-2) (2004), 215-220.
64)
Topalova S.,
Zlatarski R., Construction of doubles of the 2-(21,5,1) design with
automorphisms of order 2, Proceedings
of the Ninth International Workshop on Algebraic and Combinatorial Coding
Theory, Kranevo, Bulgaria (2004), 379-383.
65)
Topalova S., Classification
of Hadamard matrices of order 44 with Automorphisms of order 7, Discrete
Mathematics 260 (1-3) (2003), 275-283.
66)
Topalova S.,
Zlatarsky R., On STS(21) of
67)
Topalova S.,
Zlatarsky R., Construction of STS(21) of
68)
Topalova S.,
Groups of automorphisms and enumeration of combinatorial designs, Proceedings of the EWM International
Workshop on Groups and Graphs, Varna, Bulgaria (2002), 105 - 110.
69)
Topalova S.,
Zlatarsky R., Construction of STS(21) with automorphisms of order 2, Proceedings of the Third International
Workshop on Optimal Codes and Related Topics, Sunny Beach,
Bulgaria (2001), 147 - 150.
70)
Topalova S., Symmetric
2-(69,17,4) Designs with Automorphisms of order 13, J. Statistical
Planning and Inference 95 (2001), 335 - 339.
71)
Solov'eva F.,
Topalova S., Perfect
binary codes and Steiner triple systems with the maximal order of the
automorphism group, Diskretnii analis i issledovanie operatsii
series 1, vol. 7, N4 (2000), 101-110 (in Russian).
72)
Solov'eva F.,
Topalova S., On
the automorphism group of perfect binary codes and Steiner triple systems,
Problems of Information Transmission
36 (4) (2000), 331-335.
73)
Solov’eva F. I., Topalova S. T. On the automorphism groups
of perfect binary codes, Proc. Seventh Int. Workshop on Algebraic and Comb.
Coding Theory. Bansko, Bulgaria (2000), 283–287.
74)
Topalova S.,
Hadamard matrices of order 44 with automorphisms of order 7, Proceedings of the Seventh International
Workshop on Algebraic and Combinatorial Coding Theory,
Bansko, Bulgaria} (2000), 305-310.
75)
Topalova S.,
2-(51,6,2) designs with automorphisms of order 51, Proceedings of the Sixth International Workshop on Algebraic and
Combinatorial Coding Theory, Pskov, Russia (1998), 220-223.
76)
Topalova S.,
Hadamard 2-(43,21,10) designs with automorphisms of order 21 and binary
self-dual codes of lengths 86 and 88, Proceedings
of the Second International Workshop on Optimal Codes and Related Topics,
Sozopol, Bulgaria (1998), 193-197.
77)
Topalova S.,
Designs from tactical configurations, Mathematics and Education in
Mathematics (1998), 135-138.
78)
Topalova S.,
Construction and study of combinatorial designs with certain automorphisms,
Ph. D. Thesis, Sofia (1998) (in Bulgarian).
79)
Topalova S., Enumeration
of 2-(21,5,2) designs with automorphisms of an odd prime order,
Discretnyi Analis i Issledovanie operatsii (In Russian) series 1, vol.5, N1
(1998), 64-81.
80)
Kapralov S.N.,
Topalova S., Enumeration of 2-(21,6,3) Designs with Automorphisms of Order 7 or
5, Ars Combinatoria 48 (1998), 135-146.
81)
Landjev I.,
Topalova S., New
Symmetric (61,16,4) designs invariant under the dihedral group of order 10,
Serdika Mathematical Journal 24 (2) (1998), 179-186.
82)
Topalova S.,
Enumeration of 2-(25,5,2) Designs with an automorphism of order 5, Journal
of Combinatorics, Information and System
Sciences 22 (3-4) (1997), 161-176.
83)
Topalova S., On
the order of the automorphism group of 2-(40,10,3) designs, Mathematics and
Education in Mathematics (1996), 161-166.
84)
Topalova S.,
Enumeration of 2-(25,5,2) Designs with an Automorphism of order 5 with 5 fixed
points and 10 fixed blocks, Mathematics and Education in Mathematics (1997), 198-201.
85)
Topalova S.,
Enumeration of 2-(25,5,2) Designs with automorphisms of order 5 without fixed
points and with 5 or 10 fixed blocks, Proceedings of the Fifth International
Workshop on Algebraic and Combinatorial
Coding Theory, Sozopol, Bulgaria
(1996), 288-294.
86)
Topalova S.,
Enumeration of 2-(21,5,2) designs with an automorphism of order 5, Mathematics and Education in Mathematics (1995), 241-253.
87)
Topalova S.,
Enumeration of 2-(21,5,2) designs with an automorphism of order 7, Proceedings
of the Fourth International Workshop on Algebraic
and Combinatorial Coding Theory,
Novgorod, Russia (1994), 187-189.
88)
Baicheva Ts., Bogdanova
G., Ilieva S., Topalova S., Object-oriented C++ library for computations in and
over finite fields of characteristic 2, Mathematics and Education in
Mathematics (1994), 227-230.
89)
Kapralov S.N., Topalova
S., On the Steiner Triple Systems of order 21 with automorphisms of order 3, Proceedings of the Third International
Workshop on Algebraic and Combinatorial Coding Theory, V.Voda,
Bulgaria (1992), 105-108.
90)
Manev N.,
Topalova S., A software system for testing Reed-Solomon codes in different
channels, Mathematics and Education
in Mathematics (1992) (in Bulgarian), 304-306.
91)
Baicheva T.,
Topalova S., Bogdanova G., Ilieva S., Software implementation of spectral
methods for coding and decoding of BCH codes,
Mathematics and Education in Mathematics (1992) (in Bulgarian),
291-294.
Ph. D. Thesis
Topalova S., Construction and study of
combinatorial designs with certain automorphisms, Ph. D. Thesis, Sofia
(1998) (in Bulgarian).