TY  - JOUR
AU  - Day, Alan
TI  - Idempotents in The Groupoid of all SP Classes of Lattices
JO  - Canadian mathematical bulletin
PY  - 1978
SP  - 499
EP  - 501
VL  - 21
IS  - 4
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1978-085-2/
DO  - 10.4153/CMB-1978-085-2
ID  - 10_4153_CMB_1978_085_2
ER  -