The New York Times, February 18, 1968 The New York Times, February 29, 1968 "PERCY SHUNNING ACTIVE '68 ROLE – Wants to Stay Off Ballot in Presidential Primaries – Article – NYTimes.com".
בדיקה אחרונה ב-24 בנובמבר 2008. (הקישור אינו פעיל, 26.2.2019) The New York Times, February 18, 1968 The New York Times, February 29, 1968 "PERCY SHUNNING ACTIVE '68 ROLE – Wants to Stay Off Ballot in Presidential Primaries – Article – NYTimes.com".