There are some Spalthoff names included in "Milwaukee's German Newspapers; an index of death notices and related items" (1844-1950).
1911 death notices - Spalthoff, Harvey (referencing Hugo & Bertha)
1911 death notices - Spalthoff, Josephine (referencing Antonie)
Indexing Milwaukee's German newspapers continuously since 2007 ...
Gary Rebholz, compiler/editor