@article {Hanzel:1994,
	title = {What is a Category?},
	journal = {Metaphilosophy},
	volume = {25},
	year = {1994},
	pages = {181-193},
	author = {Hanzel, Igor and V{\'a}clav {\v C}ern{\'\i}k and Vicen{\'\i}k, Jozef}
}
