Collier's encyclopedia, with bibliography and index; Volume 1
P.F. Collier & Son, 1954
 Buku Referensi
Collier's encyclopedia, with bibliography and index; Volume 7
P.F. Collier & Son, 1954
 Buku Referensi
Collier's encyclopedia, with bibliography and index; Volume 17
P.F. Collier & Son, 1954
 Buku Referensi
Collier's encyclopedia, with bibliography and index; Volume 4
P.F. Collier & Son, 1954
 Buku Referensi
Collier's encyclopedia, with bibliography and index; Volume 2
P.F. Collier & Son, 1954
 Buku Referensi