Gaya APA
STALLCUP, J, G. (1990).
SIGN ELECTRICIAN'S WORKBOOK BASED ON THE 1990 NEC .
United States of America:
American Technical Publisher.
Gaya MLA
STALLCUP, JAMES, G..
"SIGN ELECTRICIAN'S WORKBOOK BASED ON THE 1990 NEC".
United States of America:
American Technical Publisher,
1990.
Text.