Gravitation and modern cosmology  the cosmological constant problem 
edited by Antonino Zichichi, Venzo de Sabbata and Norma Sanchez 
 - New York  Plenum Press  1991 
 - 228 p. : ill. ; 26 cm. 
 - Ettore Majorana international science series. Physical Sciences  v. 56 .
<br/><br/> ' Proceedings of a symposium held in honor of Peter Gabriel Bergmann,s 75th birthday, held September 17-20, 1990, in Erice, Sicily, Italy'-- T.P. verso 
<br/><br/><label>ISBN: </label>0306440547  RM224.28 
<br/><br/><label>LCCN: </label>Lc-91-40369 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Gravitation--Congresses