Gaya APA
Discovering Astronomy. (1978).
San francisco:
W.H. Freeman and Company.
Gaya Chicago
Discovering Astronomy.
.
San francisco:
W.H. Freeman and Company,
1978.
.
Gaya MLA
Discovering Astronomy.
.
San francisco:
W.H. Freeman and Company,
1978.
.
Gaya Turabian
Discovering Astronomy.
San francisco:
W.H. Freeman and Company,
1978.
.