RFCs:

[RFC 3711] The Secure Real-time Transport Protocol (SRTP).

[RFC 3830] MIKEY: Multimedia Internet KEYing.

Publications:

Hastad, J.; Naslund, Mats.
Practical Construction and Analysis of Pseduo-randomness Primitives.
2001. Proceedings of Asiacrypt 2001, LNCS. vol 2248, pp. 442 - 459