The Harvard classics : volume 33, voyages and travels: ancient and modern
Charles W. Eliot, edited
P. F. Collier & Son Corporation, 1959
 Buku Referensi
Social studies in practice : a volume of case studies
edited by R. Meurig Evans
Macmillan, 1975
 Buku Teks
Clarke, William Eagle, 1853-1938
Studies in bird migration. Volume 1
Cambridge University Press, 2014
 Buku Teks
Encyclopedia of humor studies : volume 2
editor, Salvatore Attardo
Sage, 2014
 Buku Referensi
Management men and their methods : 33 case studies in exective techniques / edited, Luis J.A. Villalon
Funk & Wagnalls Company, 1949
 Buku Teks