[1] F. Buckley: Self-centered graphs with a given radius. Proc. 10th S-E Conf. Combinatorics, Graph Theory and Computing. Boca Raton, 1979, pp. 211-215. MR 0561047 | Zbl 0426.05034

[2] F. Buckley F. Harary: Distance in Graphs. Addison-Wesley, New York, 1990, 335 pp. MR 1045632

[3] L. Caccetta: On graphs that are critical with respect to the parameters: diameter, connectivity and edge-connectivity. Matematiche (Catania) 47 (1992), 213-229. MR 1275856 | Zbl 0793.05079

[4] G. Chartrand, Songlin Tian: Distance in digraphs. Mathematics and Computer Models, Preprint, 1991, 15 pp. MR 1486881

[5] Yu Xiang Du, Lijie Shi, Xiaodong Zhao: The structure of upper radius critical graphs. J. Natur. Sci. Math. 36 (1996), 77-82. MR 1627192

[6] R. D. Dutton S. R. Medidi. R. C. Brigham: Changing and unchanging the radius of a graph. Linear Algebra Appl. 217 (1995), 67-82. MR 1322543

[7] P. Erdős J. Pach R. Pollack Z. Tuza: Radius, diameter, and minimum degree. J. Combin. Theory, Ser. B 47 (1989), 73-79. DOI 10.1016/0095-8956(89)90066-X | MR 1007715

[8] L. Fajtlowicz: A characterisation of radius critical graphs. J. Graph Theory 12 (1988), 529-533. DOI 10.1002/jgt.3190120409 | MR 0968749

[9] G. Sh. Fridman: On radially critical oriented graphs. Dokl. Akad. Nauk 212 (1973), 556-559. (In Russian.) MR 0412008

[10] F. Gliviak: On radially critical graphs. Recent Advances in Graph Theory- Proc. Symp. Prague 1974. Academia, Praha, 1975, pp. 207-221. MR 0384613

[11] F. Gliviak: On the structure of radially critical graphs. Graphs, Hypergraphs and Block Systems. Proc. Symp. Zielona Gora, Poland, 1976, pp. 69-73. MR 0384613 | Zbl 0345.05121

[12] F. Gliviak M. Knor L. Šoltés: On radially maximal graphs. Australasian J. Combin. 9 (1994), 275-284. MR 1271207

[13] F. Gliviak M. Knor L. Šoltés: Two-radially maximal graphs with special centers. Math. Slovaca 45 (1995), 227-233. MR 1361815

[14] F. Gliviak M. Knor: On radially extremal digraphs. Math. Bohem. 120 (1995), 41-55. MR 1336945

[15] N. Graham F. Harary: Changing and unchanging the diameter of a hypercube. Discrete Appl. Math. 37/38 (1992), 265-274. MR 1176857

[16] F. Harary: Changing and unchanging invariants for graphs. Bull. Malaysian Math. Soc. (2) 5 (1982), 73-78. MR 0700121 | Zbl 0512.05035

[17] F. Harary G. Thomassen: Anticritical graphs. Math. Proc. Cambridge Philos. Soc. 79 (1976), 11-18. DOI 10.1017/S0305004100052051 | MR 0414439

[18] T. W. Haynes L. M. Lawson R. C. Brigham R. D. Dutton: Changing and unchanging of the graphical invariants: Minimum and maximum degree, maximum clique size, node independence number and edge independence number. Congr. Numer. 72 (1990), 239-252. MR 1041828

[19] J. Harant: An upper bound for the radius of a 3-connected graph. Discrete Math. 122 (1993), 335-341. DOI 10.1016/0012-365X(93)90306-E | MR 1246688 | Zbl 0787.05055

[20] J. Harant H. Walther: On the radius of graphs. J. Combin. Theory, Ser. B 30 (1981), 113-117. DOI 10.1016/0095-8956(81)90101-5 | MR 0609604

[21] Katsumi Inoue: Radius of 3-connected graphs. SUT J. Math. 32 (1996), 83-90. MR 1401106

[22] Sh. M. Ismailov: The number of arcs of a digraph of a given radius with a given number of vertices and strong components. Dokl. Akad. Nauk Azerbaidzhana 27 (1971), 8-12. (In Russian.) MR 0294177

[23] Ju. Nishanov: On radially critical graphs with maximal diameter. Voprosy algebry, teorii chisel, diferencialnych i integralnych uravneniy. Samarkand State University, Samarkand, 1973, pp. 138-147. (In Russian.)

[24] Ju. Nishanov: On two classes of radially critical graphs. Voprosy algebry i teorii chisel. Samarkand State University, Samarkand, 1980, pp. 16-22. (In Russian.)

[25] Ju. Nishanov: On radially critical graphs with radius two. Modeli i algoritmy prikiadnoj matematiki. Samarkand, 1989. pp. 125-130. (In Russian.)

[26] Ju. Nishanov: On unicyclic radially critical graphs. Voprosy algebry i teorii chisel. Samarkand State University. Samarkand, 1990. pp. 54-65. (In Russian.)

[27] J. Plesnik: Graph Algorithms. Veda, Bratislava. 1983, 343 pp. (in Slovak.)

[28] Tomomi Segawa: Radius increase caused by edge deletion. SUT J. Math. 30 (1994), 159-162. MR 1311012

[29] Songlin Tian: Sum distance in digraphs. Congr. Numer. 78 (1990), 179 -192. MR 1140482

[30] Songlin Tian, Ch. E. Williams: Detour distance in digraphs. Graph Theory and Applications. Proc. Int. Conference, vol. 2, Y. Alavi. A. Schweuk (eds.). John Wiiey and Sons, 1995, pp. 1155-1165. MR 1405891

[31] V. G. Vizing: On the number of edges in a graph with given radius. Dokl. Akad. Nauk 173 (1967). 1245-1246. (In Russian.) MR 0210622

[32] A. A. Zykov: Fundamentals of Graph Theory. Nauka. Moskva, 1987, 381 pp. (In Russian.) MR 0909295