Was Martin Luther a Closet Universalist?
A quote from a letter of a Hans von Rechenberg seems to suggest Luther may have believed in after death salvation. Florian Berndt, a German, researches this quote out in the original German.

Universalism History
Article from Cyclopedia of Biblical, Theological, and Ecclesiastical Literature , Volume 10, 1895, pp. 109-33, Rev. John McClintock and James Strong.

Brief History of Universalism
Short article by Rev. J.M. Austin in Biblical Repository, ca. 1855