1. Stojan M. Bogdanović, Petar V. Protić, Blagoje T. Stamenković: Matematika I, Prosveta, Nis, 1995, drugo izdanje 1977.
2. Petar V. Protić, Blagoje T. Stamenković: Zbirka rešenih zadataka iz Matematike I, Tibet, Niš, 1996.
3. Petar V. Protić, Blagoje T. Stamenković, Slobodan B. Tričković: Zbirka zadataka iz Matematike I, GAF Niš, 1998.
4.Svetlana V. Janković, Petar V. Protić, Katica (Stevanović) Hedrih: Parcijalne diferencijalne jednačine i integralne jednačine, Univerzitet u Nišu, 1999.
5. P. Protić, B. Stamenković, S. Tričković, N. Stevanović: Zbirka rešenih zadataka sa prijemnih ispita na GAF-u Niš, 2004.
6. Petar Protić, Slobodan Tričković, Blagoje Stamenković: Matematika 2, Tibet, Niš, 2005.
7. Petar V. Protić: Matematika I, GAF Niš, 2012.
8. Petar V. Protić: Zbirka zadataka iz matematike I, GAF Niš, 2012.
1. P. V. Protić: On some band decompositions of semigroups, Publicationes mathematicae, Debrecen, 45 (1994), 205-211.
2. P. V. Protić: Bands of right simple semigroups, Publicationes mathematicae, Debrecen, 47 (1995), 311-313.
3. N. Stevanović and P. Protić: Structure of Weakly Externally Commutative Semigroups, Algebra Colokvijum 13:3 (2006), 441-446.
1. P. Protić and S. Bogdanović: Some idempotent-separating congruences on a pi-regular semigroup, Note di Matematica VI, Lecce (1986), 253-272.
2. P. Protić and S. Bogdanović: Some congruences on a strongly pi-inverse r-semigroup, Zbornik radova PMF Novi Sad (1985), 79-89.
3. B. Stamenković and P. Protić: The natural partial orderon an r-cancelative semigroup, Matematički vesnik 39, 1987, 455-462.
4. B. Stamenković and P. Protić: On the compatibilityof the natural partial order on an r-cancelative r-semigroup, Zbornik radova Filozofskog fakulteta u Nišu, Serija matematika 1(11), 1987, 79-87.
5. P. V. Protić: Some congruences on a pi-regular semigroup, Facta Universitatis, Ser. Math. Inform. 5, 1990, 19-24.
6. P. V. Protić: The band and the semilattice decompositions of some semigroups, PU. M. A. Budapest-Siena, Ser. A 2 No.1-2, 1991, 141-146.
7. P. V. Protić and M. Božinović: Some congruences on a pi-regular semigroup, FILOMAT 20, 6, 1992, 175-180.
8. P. V. Protić: A new proof of Putcha's theorem, PU. M. A. Budapest-Siena, Ser. A 2 No.3-4, 1991, 281-284.
9. P. V. Protić: On some type of radicals on a semigroup, Matematički vesnik, 1991, 23-28.
10. M. Božinović and P. V. Protić: Congruences on a pi-inverse LA*- semigroups, Facta Universitatis (Niš), Ser. Math. Inform. , 1994, 19-29.
11. N. Stevanović and P. Protić: The structural theorem for AG*-groupoids, Facta Universitatis (Niš), Ser. Math. Inform. 10 (1995), 25-33.
12. P. V. Protić and M. Božinović: Some congruences on an AG**-groupoids, FILOMAT 9:3 (1995), 879-886.
13. P. V. Protić and N. Stevanović: AG-test and some general properties of Abel-Grassmann's groupoids, PU. M. A. Budapest-Siena, Ser. A, vol 6 No.4, (1995), 371-383.
14. M. Božinović, P. V. Protić and N. Stevanović: The natural partial order on the Abel-Grassmann's groupoids, Filomat 10 (1996), 107-116.
15. P. V. Protić: Bands of Nil-Extensions of Right Simple Semigroups, Publications de l'institut mathematique, tome 62 (76), 1997, 41-45.
16. N. Stevanović and P. Protić: Some decompositions on Abel-Grassmann's groupoids, PU. M. A., Vol. 8, No. 2-3, (1997), 355-366.
17. N. Stevanović and P. Protić: Inflatons of Abel-Grassmann's groupoids, Novi Sad J. Math., No. 1 Vol 29 (1999), 19-26.
18. N. Stevanović and P. Protić: Bands decompositions of Abel-Grassmann's groupoids, PU. M. A., No. 4 Vol. 12 (2001), 431-436.
19. P. Protić and N. Stevanović: Some relations on Abel-Grassmann's 3-bands, PU. M. A., No. 1 Vol. 14 (2003),
20. N. Stevanović and P. Protić: Abel-Grassmann's bands, Quasigroups and Related Systems, Kišinjev, No. 11 (2004), 95-101 .
21. N. Stevanović and P. Protić: Composition of Abel-Grassmann's 3-bands, Novi Sad J. Math., No. 2 Vol. 34 (2004), 175-183.
22. M. Božinović, P. V. Protić and N. Stevanović: Kernel Normal System of Inverse AG**-Groupoids, Quasigroups and Related Systems, No. 17 (2008), 1-8.
23. P. V. Protić and N. Stevanović: Some decompositions of semigroups, Matematički Vesnik, 61 (2009), 153-158.
24. P. Protić: Congruences on an Inverse AG**-Groupoid via the Natural Partial Order, Quasigroups and Related Systems (17), No. 2 (2009), 283-290.
25. P. Protić: Some remarks of medial groupoids, Facta Universitatis (Niš), Ser. Math. Inform. 26 (2011), 65-73.
26.P. V. Protić: Some remarks on Abel-Grassmann's groups, Quasigroups and Related Systems 20 (2012), 141-148.
27. P. V. Protić: Some remarks on paramedial semigroups, Matematički Vesnik (2013)
1. P. Protić and S. Bogdanović: A structural theorem for (m,n)-ideal semigroups, Proc. of the szmp. n-ary structures, Skopje (1982), 135-139.
2. P. Protić and N. Stevanović: Abel-Grassmann's bands and 3-bands, Proc. of 4yh Intern. Pure. Math. Conf., Islamabad (1997), 89-102.
3. N. Stevanović and P. Protić: Roots of AG-bands, In: Approximation and Computation - In Honor of Gradimir V. Milovanović (W. Gautschi, G. Mastroianni, Th. M. Rasias, eds.) pp. 439-445, Springer Opimization and Its Applications, Springer Verlag, Berlin-Heielberg-New York, 2010.
1. P. Protić and S. Bogdanović: On a class of semigroups, Algebraic conference, Novi Sad (1981), 113-119.
2. S. Bogdanović, P. Kržovski, P. Protić and B. Trpenovski: Bi and quasi-ideal semigroups with n-property, Third Algebraic Conference, Beograd (1982), 27-34.
3. P. Protić and S. Bogdanović: The lattice of r-semiprime idempotent-separating congruences on r-semigroup, Proc. of the Conference "Algebra and Logic", Cetinje (1986), 157-165.
4. M. Božinović and P. Protić: Some congruences on a pi-regular semigroup II, Proc. of the Conference "Algebra and Logic", Maribor (1989), 21-28.
5. P. Protić: A note on right seminormal band of right simple semigroups, Proc. of the Math. Conf., Priština (1994), 27-29.
6. P. Protić and N. Stevanović: On Abel-Grassmann's groupoids (exposition) , Proc. of the Math. Conf., Priština (1994), 31-38.