@article{10_4064_cm_56_1_1_17,
     author = {Peter M. Higgins},
     title = {Epimorphisms and amalgams},
     journal = {Colloquium Mathematicum},
     pages = {1--17},
     publisher = {mathdoc},
     volume = {56},
     number = {1},
     year = {1988},
     doi = {10.4064/cm-56-1-1-17},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-56-1-1-17/}
}