Reference etiquatte:a guide to excruciatingly correct bahavior
 Artikel Jurnal
Shurter, Robert L.
Handy grammar reference: a guide to better English / Robert L. Shurter
McGraw-Hill, 1959
 Buku Teks
The Officers guide: a ready reference on customs and correct procedures which pertain to commissioned officers of the Army of the United States
Military Service Pub Co, 1950
 Buku Teks
Cameron hydraulic data : a handy reference on the subject of hydraulics
Ingersoll-Rand Company, Cameron Pump Division, 1939
 Buku Teks
Evans, Graham, author
The dictionary of world politics : a reference guide to concepts, ideas, and institutions
Harvester Wheatsheaf, 1990
 Buku Referensi