TY  - JOUR
AU  - Rowe, K. A.
TI  - Images in Topoi
JO  - Canadian mathematical bulletin
PY  - 1977
SP  - 471
EP  - 478
VL  - 20
IS  - 4
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1977-070-4/
DO  - 10.4153/CMB-1977-070-4
ID  - 10_4153_CMB_1977_070_4
ER  -