Brouwer, A. E. "Perkel Graph." http://www.win.tue.nl/~aeb/graphs/Perkel.html.Brouwer, A. E.; Cohen, A. M.; and Neumaier, A. "The Perkel Graph for ." §13.3 in Distance
Regular Graphs. New York: Springer-Verlag, pp. 401-403, 1989.Coolsaet,
K. and Degraer, J. "A Computer Assisted Proof of the Uniqueness of the Perkel
Graph." Designs, Codes and Crypt.34, 155-171, 2005.DistanceRegular.org.
"Perkel Graph." http://www.distanceregular.org/graphs/perkel.html.Neumann,
P. M. "Permutationsgruppen von Primzahlgrad und verwandte Themen."
Vorlesungen Math. Inst. Giesen, Heft 5, 1977.Perkel, M. "Bounding
the Valency of Polygonal Graphs with Odd Girth." Canad. J. Math.31,
1307-1321, 1979.Perkel, M. "Characterization of in Terms of Its Geometry." Geom. Dedicata9,
291-298, 1980.van Dam, E. R. and Haemers, W. H. "Spectral
Characterizations of Some Distance-Regular Graphs." J. Algebraic Combin.15,
189-202, 2003.