Singapore. Telecommunications Dept. Annual report. Govt. Printing Office.
Chicago-referens (17:e uppl.)Singapore. Telecommunications Dept. Annual Report. Singapore: Govt. Printing Office.
MLA-referens (8:e uppl.)Singapore. Telecommunications Dept. Annual Report. Govt. Printing Office.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.