Major correspondents include those individuals who were considered important personalities in the 1900's-1940's, with whom Hendrik wrote irregularly (less than ten letters). This material is listed alphabetically and includes number of letters and inclusive dates. Also included in this series are draft copies of correspondence and microfilmed correspondence.

Major correspondents include those individuals who were considered important personalities in the 1900's-1940's, with whom Hendrik wrote irregularly (less than ten letters). This material is listed alphabetically and includes number of letters and inclusive dates. Also included in this series are draft copies of correspondence and microfilmed correspondence.

Major correspondents include those individuals who were considered important personalities in the 1900's-1940's, with whom Hendrik wrote irregularly (less than ten letters). This material is listed alphabetically and includes number of letters and inclusive dates. Also included in this series are draft copies of correspondence and microfilmed correspondence.

Major correspondents include those individuals who were considered important personalities in the 1900's-1940's, with whom Hendrik wrote irregularly (less than ten letters). This material is listed alphabetically and includes number of letters and inclusive dates. Also included in this series are draft copies of correspondence and microfilmed correspondence.