CPH to Speyer & Co., June 20, 1893 (seven separate letters), HEH Collection.
C. F. Crocker to CPH, June 19, 1893 CPH Papers, ser.1, r. 52.
Salomon to CPH, June 20, June 21, 1893 CPH Papers, ser.1, r. 52.
Speyer & Co. to CPH, June 14, 1893, CPH Papers, ser. 1, r. 52.
Crocker to CPH, June 21, June 22, 1893, CPH Papers, ser. 1, r. 52.
C. F. Crocker to CPH, c. June 26, 1892, CPH Papers, ser. 1, r. 52.
CPH to T. Hubbard, March 7, 1894, CPH Papers, ser. 1, r. 50.
C. F. Crocker to CPH, July 5, 17, 1893, H. Spencer to CPH, Aug. 10, 1893, CPH Papers, ser. 1, r. 52.
C. F. Crocker to CPH, Dec. 22, 1893CPH Papers, ser. 1, r. 52.