What typeface is Gerritszoon supposed to be?
Griffo Gerrtiszoon is almost certainly a merger of Francesco Griffo (the designer of typefaces at the Aldine Press) and Gerrit Gerritszoon (aka Erasmus, who worked for the Aldine Press as a Greek scholar).
We are told Gerritszoon was included on the Mac.
There is one typeface inspired by Francesco Griffo that has long been included on the Mac: Hermann Zapf's Palatino.
Interestingly Zapf considered Palatino a display typeface and designed a book weight complement called...wait for it...Aldus :-)
So I guess one could argue Zapf's Aldus is really Gerritszoon and Palatino is Gerritszoon Display.
But I think Palatino is most likely the typeface Sloan intended Gerritszoon to represent.
EDIT: see below