@article{10_1090_S0894_0347_2013_00776_6,
     author = {Sapir, Mark},
     title = {A {Higman} embedding preserving asphericity},
     journal = {Journal of the American Mathematical Society},
     pages = {1--42},
     publisher = {mathdoc},
     volume = {27},
     number = {1},
     year = {2014},
     doi = {10.1090/S0894-0347-2013-00776-6},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-2013-00776-6/}
}