Maybe these grammar sources are of help too:
 
any: determiner and pronoun - indicates an indefinite quantity of something
 
any + of + noun phrase
 
Have you read any of her books?
I don �t like any of his music
Do any of you speak German
 
to refer to one or several people or things, or to part of something
 
(Scott Thornbury - Natural Grammar p 10)
 
 
When any of is followed by a plural subject, the verb can be singular or plural.  A singular verb is more common in formal style.  
 
If any of your friends is/are interested, let me know
 
(Michael Swan, Practical English Usage p 57)