This appears to be the correct cemetery according to where the memorial was held.
Howard E. Hart married May M. Dolson 10 Sep 1906 in Los Angeles, California.
in 1910 next door to May's parents, Martin O. Dolson and Christina Dolson
1910 census California Los Angeles County, Los Angeles Twp
Howard Hart head mw 30 m1 3 Michigan US US carpenter house
Margaret Hart wife fw 27 m1 3 0,0 KS IN KS teacher music

World War I registrar
Howard Edward Hart b
born April 27,1879
occupation medical student
contact wife:
May Margarette Hart 137 East 25th Street Los Angles CA

in 1920 next door to Martin O. Dolson and Christina Dolson
1920 census California Los Angeles County Los Angeles Twp Los Angeles city
H.E. O.D. Hart head mw 40 m Michigan blank blank Oktom OD Home office
May M. Hart wife fw m KS IN KS
Edna M Hart dau fw s CA Michigan KS
voter list:
1928
Howard E. Hart 137 E. 25th Street.
1930--- no census has been found.
voter lists:
1930
Howard E. Hart 137 E. 25th Street
1934 same
1936 same
1938
Howard E. Hart 137 E. 25th Street
Mrs. May M. Hart 137 E. 25th Street
1942 same as 1938
1944 same as 1938

Daughter --Edna May Hart married Paul Rex Hansen Jan 29, 1938 Orange County, CA. parents:hers- Howard E. Hart MD and May M. Dolson his- Cliver Hansen and May Hoyer

in 1940 next door to Martin O. Dolson and Christia Dolson
1940 census California Los Angeles County Los Angeles Twp Councilmanic district 10

May M Hart head fw 57 KS same house in 1935
Christina Hart dau fw 19 CA same house in 1935
Marguerite Hart dau fw 18 CA same house in 1935

Daughter-- Christina Annnetta Hart married Elmer Richard Swatsley Feb. 9, 1941 in Orange County, CA. parents: hers-Howard E. Hart and May Marguerite Dolson his-Ellmer Swatsley and Edwinnie DeCamp

Daughter-- Marguerite Elizabeth Hart married Raymond Reed Flick Oct.4, 1941 in Los Angeles County, CA. parents: hers-Howard E. Hart and May M. Dolson his-Raymond A. Flick and Madelene G. Holmes