共 5 条
[1]
Behzad M., 1979, GRAPHS DIGRAPHS
[3]
Dirac G. A., 1952, P LOND MATH SOC, V2, P69, DOI [10.1112/plms/s3-2.1.69, DOI 10.1112/PLMS/S3-2.1.69]
[5]
Ore O., 1960, AM MATH MON, V67, P55, DOI [10.2307/2308928, DOI 10.2307/2308928]