Gaya APA
Bettger, Frank. (1994).
How I multiplied my income and happiness in selling .
Britain:
Mandarin.
Gaya Chicago
Bettger, Frank.
How I multiplied my income and happiness in selling.
Britain:
Mandarin,
1994.
Text.
Gaya MLA
Bettger, Frank.
How I multiplied my income and happiness in selling.
Britain:
Mandarin,
1994.
Text.
Gaya Turabian
Bettger, Frank.
How I multiplied my income and happiness in selling.
Britain:
Mandarin,
1994.
Print.