When Martin's mother, Mary Blank (played by Barbara Harris), is seen in a mental hospital babbling incoherently, she exits stage right and recites several lines from a poem followed by the line "Silly. Bye, Martin". The poem is actually a distortion of the last few lines of The Ladies by Rudyard Kipling.

Mary says:

The Colonel's lady, like Judy O'Grady
Are twins under the skin!

Kipling's original text:

For the Colonel’s lady an’ Judy O’Grady,
Are sisters under their skins!

You can find the poem in it's entirety at http://www.everypoet.com/archive/poetry/Rudyard_Kipling/kipling_the_ladies.htm