APA
A. Murray Harper, . (1981). Nature. U.S.A: Macmillan Journals Ltd.
Chicago
A. Murray Harper, . 1981. Nature. U.S.A: Macmillan Journals Ltd.
Harvard
A. Murray Harper, . (1981). Nature. U.S.A: Macmillan Journals Ltd.
MLA
A. Murray Harper, . Nature. U.S.A: Macmillan Journals Ltd. 1981.