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.
C. F. Crocker to CPH, June 28, 1892 CPH Papers, ser. 1, r. 52.
C. F. Crocker to CPH, June 28, 14, 1892 (letter and telegram), June 19, 30, July 5 (two letters), 1893, CPH to C. F. Crocker, June 16, 1893, all in CPH Papers, ser. 1, r. 52.
CPH to C. F. Crocker, July 7, 1893, CPH Papers, ser. 1, r. 52.