What is the recommended temperature for a racquetball court?

The World Squash Federation recommends:

12.1 It is recommended that a Squash court and any adjacent spectator areas (including the space for the marker and referee) shall be provided with a heating and/or air conditioning system which is capable of maintaining a temperature of between 10 and 25 degrees Celsius with an ideal range of 15 to 20 degrees Celsius. That is 59-68 degrees