Like any other popular series the Planet of the apes was subject to spoofs and being pulled into other shows as an influence of a backdrop.
They had a spot in the sci-fi spoof Spaceballs.
A Planet of the apes musical took place in the Simpsons.
Mystery Science Theater 3000 had an Apes inspired character in Professor Bobo.
Even Cher appeared with Apes.
In earlier seasons of Welcome Back, Kotter you may notice Arnold Horshack carrying this lunchbox.
Feel free to add any other references that you know of.