universal constructions '' pub henry helson crescent berkeley ca pp nbsp birkhoff garrett universal algebra ''comptes rendus du premier congr canadien de math matiques'' university toronto press toronto pp nbsp burris stanley n hp sankappanavar '' http wwwthoralfuwaterlooca htdocs ualghtml course universal algebra '' springer verlag ''free online edition'' cohn paul moritz ''universal algebra'' dordrecht netherlands dreidel publishing '' first published harper row '' freese ralph ralph mckenzie '' http wwwmathhawaiiedu ralph commutator commutator theory congruence modular varieties st ed london mathematical society lecture note series cambridge univ press free online second edition''
Formal science Mathematics Pure mathematics Algebra Universal algebra