Gaya APA
1970 Nature/Science Annual. (1969).
Canada:
Life-Time Books.
Gaya Chicago
1970 Nature/Science Annual.
.
Canada:
Life-Time Books,
1969.
.
Gaya MLA
1970 Nature/Science Annual.
.
Canada:
Life-Time Books,
1969.
.
Gaya Turabian
1970 Nature/Science Annual.
Canada:
Life-Time Books,
1969.
.