Maximal Chains of Partial Clones Containing All Idempotent Partial Functions.

Lucien Haddad Jean Fugère Maximal Chains of Partial Clones Containing All Idempotent Partial Functions. 80-84 1999 ISMVL http://computer.org/proceedings/ismvl/0161/01610080abs.htm db/conf/ismvl/ismvl1999.html#HaddadF99