Translation:Mishnah/Seder Nezikin/Tractate Avodah Zarah/Chapter 1/7

English Translation
 One can not sell to them (to gentiles) bears, lions, or anything that can do harm to the public. One cannot build with them a basilica, a scaffold, a stadium, or a stage. But one can build with them public bathhouses or private ones. When they reach the place where they stand an object of idol worship, it is forbidden to help. 

Explanation
עבודה זרה פרק א משנה ז