(1968). Recent acquisitions 1968: July - August 1968 / Marlborough Fine Art (London) Limited.
Chicago-viite (17. p.)Recent Acquisitions 1968: July - August 1968 / Marlborough Fine Art (London) Limited. London, 1968.
MLA-viite (8. p.)Recent Acquisitions 1968: July - August 1968 / Marlborough Fine Art (London) Limited. 1968.
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