Free Space loss formula Reference

Hi all,

I am looking for the reference for free space formula
fspl = 10 log 10 (4piR/lamda)^2

I guess it is in Rappaport, can anyone confirm this if he or she has the book.

thanks in advance

Friis transmission equation - Wikipedia, the free encyclopedia

Thanks Vfone. The actual reference is

Theodore Rappaport Cloth,"Wireless Communications: Principles and Practice", 2nd Edition , 2002

Thanks for helping