Gaya APA
Roth, A, C.
(1985).
Small Gas Engines
(
Edisi 4)
.
USA:
The GoodHeart-Willcox Company.
Gaya MLA
Roth, Alfred, C..
"Small Gas Engines".
Edisi 4
USA:
The GoodHeart-Willcox Company,
1985.
Buku Referensi.