GSOC Past Presidents, Book One - The physical book is part of the historic GSOC archives, and has been scanned and collected into a series of web archive pages. The book and descriptions of the earliest GSOC presidents was assembled around 1950. The GSOC obituary for founder and twice-President E.T. Hodge, written in 1970, can be found in the History page of the GSOC About tab. His newspaper obituary is found under his 1950 presidency description.
GSOC Past Presidents, Book Two - Bear in mind when reading the presidents' bios that these were written at the time that the books were assembled and usually authored by each president. So information written as "current" is not current today but current at the time of writing.
GSOC Past Presidents, Book Three - This archive really begins with Past President Evelyn Pratt in 1992.