TY  - JOUR
AU  - Lambek, J.
TI  - Grammar as Mathematics
JO  - Canadian mathematical bulletin
PY  - 1989
SP  - 257
EP  - 273
VL  - 32
IS  - 3
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1989-039-x/
DO  - 10.4153/CMB-1989-039-x
ID  - 10_4153_CMB_1989_039_x
ER  -