No Inv.: 10728-10732/P/Perp/97/5c
No Inv.: 11206/P/Perp/98/1c~78/P/Perp/97/1c~12122/P/Perp/98/1c~3417/P/Perp/99/1c
Bibliografi : hlm. 299-301
Bibliografi : hlm. 292-298
Bibliografi : hlm. 203-211
No Inv.: 11125/P/Perp/98/1c~116858/P/Perp/09/1c
No Inv.: 11861/P/Perp/98/1c
Judul asli : "Human Relationship Skill"
No Inv.: 393/P/Perp/98/1c