@article {MR2203510,
	title = {Congruences on monoids of order-preserving or order-reversing transformations on a finite chain},
	journal = {Glasg. Math. J.},
	volume = {47},
	number = {2},
	year = {2005},
	pages = {413{\textendash}424},
	issn = {0017-0895},
	doi = {10.1017/S0017089505002648},
	url = {http://dx.doi.org/10.1017/S0017089505002648},
	author = {Fernandes, V{\'\i}tor H. and Gomes, Gracinda M. S. and Jesus, Manuel M.}
}
