@article{1102983450, author = {Comer, S. D.}, title = {Classes without the amalgamation property.}, journal = {Pacific J. Math.}, volume = {31}, number = {3}, year = {1969}, pages = { 309-318}, language = {en}, url = {http://dml.mathdoc.fr/item/1102983450} }
Comer, S. D. Classes without the amalgamation property.. Pacific J. Math., Tome 31 (1969) no. 3, pp. 309-318. http://gdmltest.u-ga.fr/item/1102983450/