TY  - JOUR
AU  - MICHAEL FREEDMAN
AU  - VYACHESLAV KRUSHKAL
TI  - ENGEL RELATIONS IN 4-MANIFOLD TOPOLOGY
JO  - Forum of Mathematics, Sigma
PY  - 2016
VL  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.1017/fms.2016.20/
DO  - 10.1017/fms.2016.20
LA  - en
ID  - 10_1017_fms_2016_20
ER  -