Gaya APA
Nainggolan,SH.,MH, D, Y, C, S, D, D, B. (1980).
Management (8).
Singapore:
McGraw Hill Book Compay.
Gaya MLA
Nainggolan,SH.,MH, Dr.Tofik, Yanuar, Chandra,, SH.,MH, Dan, Dr., Bernard.
"Management".
8
Singapore:
McGraw Hill Book Compay,
1980.
Text.