Hi Marsha, Generally the cemetery information is in the obituary or the death certificate. Benjamin and Zella both died in Los Angeles County and finding an obituary there is VERY difficult because of the MANY towns, cities and newspapers.
Do you know where they lived before they died?
I checked findagrave.com but they're not listed there.
You can check interment.net/us/ca/orange.htm which has a list of cemeteries in Orange Co.
Last step to find them is to order copies of the death certificates which may or may not have the cemetery listed in the Burial field. Since they died in Los Angeles Co., you'd need to contact Los Angeles Co., http://lavote.net/recorder/BDM_Records.cfmhttp://lavote.net/recorder/BDM_Records.cfm . There is always other interesting info on a death certificate. Successful Searching!