MESI Protocol
"A low-overhead coherence solution for multiprocessors with private cache memories",
Patel, Papamarcos, ISCA 84
http://delivery.acm.org/10.1145/810000/808204/p348-papamarcos.pdf?ip=130.126.255.246&id=808204&acc=ACTIVE%20SERVICE&key=AAE16B9BF97F192F%2E4D4702B0C3E38B35%2E4D4702B0C3E38B35%2E4D4702B0C3E38B35&CFID=750098232&CFTOKEN=92994666&__acm__=1454527925_bb592e472d9f9d050585cd09fccb5817

Firefly Protocol
"Firefly, A Multiprocessor Workstation"
Thacker et al, 1987
http://research.hp.com/techreports/Compaq-DEC/SRC-RR-23.pdf

Directory
"A New Solution to Coherence Problemsin Multicache Systems"
Censier and Feautrier,
https://www.researchgate.net/publication/3046972_A_New_Solution_to_Coherence_Problems_in_Multicache_Systems

"The SGI Origin: a ccNUMA highly scalable server"
Laudon and Lenoski, ISCA 1997
http://www.sgidepot.co.uk/origin/isca.pdf

"The Stanford DASH Multiprocessor"
Gupta et al, IEEE 1992
http://users.ece.gatech.edu/~leehs/ECE6100/papers/dash.pdf

Dir-CV
"Reducing memory and traffic requirements for scalable directory-based cache coherence schemes"
Gupta et al, ICCP 1990
http://link.springer.com/chapter/10.1007%2F978-1-4615-3604-8_9