Essef - An unusual science fiction novel by the highly praised author of 'The Gameplayers of Zan'. Fraesch arrived on the planet Mulcahen to replace a missing scientist at Halcyon Station. That was the name of the very isolated and weirdly constructed laboratory on Speculations, Inc. What was going on there was not clear. The owners of the planet are shadowing Fraesch from the moment of his arrival...
Used availability for M A Foster's Waves
March 1983 : USA Mass Market Paperback
October 1980 : USA Mass Market Paperback