Kottler, M. J. Charles Darwin and Alfred Russel Wallace: Two decades of debate over natural selection / Malcolm Jay Kottler. The Darwinian heritage : [incl. proceed. of the Charles Darwin Centenary Conference, Florence Center for the History and Philosophy of Science, June 1982].(1985).

Kottler, Malcolm Jay. "Charles Darwin and Alfred Russel Wallace: Two Decades of Debate over Natural Selection / Malcolm Jay Kottler." The Darwinian Heritage : [incl. Proceed. of the Charles Darwin Centenary Conference, Florence Center for the History and Philosophy of Science, June 1982].(1985) .

Kottler, Malcolm Jay. "Charles Darwin and Alfred Russel Wallace: Two Decades of Debate over Natural Selection / Malcolm Jay Kottler." The Darwinian Heritage : [incl. Proceed. of the Charles Darwin Centenary Conference, Florence Center for the History and Philosophy of Science, June 1982].(1985), .