@article{GDZPPN001250205,
title = {Viewing results on ...-indecomposable semigroups as solutions to mathematical puzzles.},
journal = {Semigroup forum},
volume = {7},
year = {1974},
pages = {181-183},
zbl = {0292.20059},
url = {http://dml.mathdoc.fr/item/GDZPPN001250205}
}
Putcha, M.S. Viewing results on ...-indecomposable semigroups as solutions to mathematical puzzles.. Semigroup forum, Tome 7 (1974) pp. 181-183. http://gdmltest.u-ga.fr/item/GDZPPN001250205/