There is another relevant publication:
 
Moritz RFA and Southwick EE 1992 Bees as superorganisms. An
evolutionary reality. Published by Springer, Berlin, Heidelberg,
New York.
 
 
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Michael Haberl
Zoologisches Institut der Uni Muenchen         Tel: ++49 89 5902-444
Luisenstr. 14                                  Fax: ++49 89 5902-450
80333 Muenchen, Germany   E-mail: [log in to unmask]
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