共 8 条
[2]
RECURSIVELY ENUMERABLE DEGREES AND CONJUGACY PROBLEM
[J].
ACTA MATHEMATICA UPPSALA,
1969, 122 (1-2)
:115-&
[3]
Higman G., 1949, J LOND MATH SOC, V26, P247
[5]
MILLER CF, 1971, ANN MATHEMATICS STUD, V68
[7]
van Kampen ER, 1933, AM J MATH, V55, P268