Call of Cthulhu (d20 Edition Horror Roleplaying, WotC), by Monte Cook, John Tynes
Call Of Cthulhu: Horror Roleplaying In the Worlds Of H.P. Lovecraft (5th Edition - Chaosium #2336), by Petersen, Sandy, Willis, Lynn
Cthulhu Now: Modern Adventures and Background for Call of Cthulhu Roleplaying/3307, by Petersen,Okamoto, Jeff,Herber, Keith,Corless, Peter,Barton, William A.
Investigator's Companion vol. 2 (Call of Cthulhu Horror Roleplaying, 1920s, #2346), by Herber, Keith, Ross, Kevin A., Rucka, Greg, O'Connell, Gary
The Bermuda Triangle (Call of Cthulhu Horror Roleplaying, 1990s Era), by Justin Schmid