What is the specific heat capacity of a racquetball?

I need an estimation of it…I’m doing a physics lab on the conservation of energy, and I need to calculate the change in temperature of a racquetball.
Or better yet, anyone know where I might possibly go to find out?

http://www.pennracquet.com/balls/racq.html

N. Bekkedahl and H. Matheson, Heat Capacity, Entropy, and Free Energy of Rubber Hydrocarbon. J. Res. Natl. Bur. Stand., 15, 503 (1935).

Do you think that using the specific heat of rubber in general would suffice?

Jesus, I have no idea but that question is just too strange not to have a look.