TY  - JOUR
AU  - Raphael M. Robinson
TI  - Undecidability and Nonperiodicity for Tilings of the Plane.
JO  - Inventiones mathematicae
PY  - 1971
SP  - 177
EP  - 209
VL  - 12
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM_1971__12_142073/
ID  - IM_1971__12_142073
ER  -