Perry's Index to the Aesopica
Fables exist in many versions; here is one version in English:
THE FOX AND THE WEASEL
It happened that a slender fox had made her way through a narrow crack into
a coffer of grain. After eating her fill, she wanted to get back out again but
her swollen body prevented her from doing so. At a safe distance the weasel
said to her, 'If you want to get out of there, you better be as thin when you
go back through that narrow crack as you were when you went in!'
Aesop's Fables. A new translation by Laura
Oxford University Press (World's Classics): Oxford, 2002.
cover, with new ISBN, published in 2008; contents of book unchanged.
Perry 24: Gibbs (Oxford) 443 [English]
Perry 24: Townsend 134 [English]
Perry 24: Babrius 86 [Greek]
Perry 24: Chambry 30 [Greek]
You can find a compilation of Perry's index to the Aesopica in the gigantic appendix to his
edition of Babrius and Phaedrus for the Loeb Classical Library
(Harvard University Press: Cambridge, 1965). This book is an absolute must for anyone interested
in the Aesopic fable tradition. Invaluable.