^*Susanna Åkerman, "Rose cross over the Baltic: the spread of rosicrucianism in Northern Europe", Brill's studies in intellectual history 87, Brill, 1998, ISBN90-04-11030-5, p. 216.
^*Johannes Kepler (translated and edited by Edward Rosen), "Kepler's somnium: the dream, or posthumous work on lunar astronomy", Courier Dover Publications, 2003, ISBN0-486-43282-3, p. 184.
^*William R. Newman, Anthony Grafton, "Secrets of nature: astrology and alchemy in early modern Europe", Transformations: Studies in the History of Science and Technology, MIT Press, 2001, ISBN0-262-14075-6, p. 301.