edited by P. Hansen
North-Holland, 1981
Buku Teks
Chartrand, Gary
Prindle, Weber & Schmidt , 1977
Buku Teks
Kevin Kamal, author
2017
UI - Skripsi (Membership)
Rahima Fitriani, author
Universitas Indonesia, 2017
UI - Skripsi (Membership)
M. Haryono, author
Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2012
UI - Tesis (Open)