Ayer, Alfred J.1 // Voltaire (англ.). — Weidenfeld & Nicolson, 1986. — P. 19. — ISBN 0 297 78880 9. «For some time Voltaire had been writing affectionately to his elder niece, Madame Denis, and from his letters — tracked down, translated and published by the indefatigable Mr. Besterman …»
"Science: Houdini, Doyle". Online archive. Time magazine. 31 марта 1930. Архивировано 27 декабря 2009. Дата обращения: 29 ноября 2009. After reviewing the performance of the medium. Besterman concluded: «To put forward such a book as this as a serious contribution to psychical research … with such claims of infallibility … is to bring our subject into contempt and disrepute».
"Science: Houdini, Doyle". Online archive. Time magazine. 31 марта 1930. Архивировано 27 декабря 2009. Дата обращения: 29 ноября 2009. After reviewing the performance of the medium. Besterman concluded: «To put forward such a book as this as a serious contribution to psychical research … with such claims of infallibility … is to bring our subject into contempt and disrepute».
