CPH to C. F. Crocker, July 7, 1893, CPH Papers, ser. 1, r. 52.
C. F. Crocker to CPH, June 28, 1893, Crocker to CPH, July 26, 1893 CPH Papers, ser. 1, r. 52.
CPH to C. F. Crocker, July 18, 1893, CPH Papers, ser. 1, r. 52.
CPH to C. F. Crocker, July 17, 12, 1893, C. F. Crocker to CPH, July 26, 12, 1893, CPH Papers, ser. 1, r. 52.
Mahl, "Memoirs: P.I. Co.," G4, Mahl Papers.
C. F. Crocker to CPH, July 26, 1893 CPH Papers, ser. 1, r. 52.