I don't think I understand what you mean by the "primary source".
If you are referring to the primary source of information on PPXII, the answer is
Sr. Margherita Marchione.
She is the ultimate expert on PPXII as acknowledged by the Vatican.
Check out her web site. She has written many books on PPXII.
www.Sr. Margherita Marchione.com
It was Pius XII. He was pope from Mar. 2, 1939 to his death on Oct. 9, 1958.
Pope Pius XII is 6'.
Pope Pius XII was born on March 2, 1876.
Pope Pius XII was born on March 2, 1876.
Pius XII became pope on March 2, 1939.
Testament of Pope Pius XII was created in 1956.
Pope Pius XII followed Pius XI.
Pius XII was elected on March 2, 1939.
Pope John XXIII followed Venerable Pius XII.
Pope Pius XII - Cardinal Cushing - was created in 1959.
Pope Pius XII died on October 9, 1958 at the age of 82.
There has never been a Pope Pius XVI. Pius XII was the last pope by that name.