Personal correspondence: K Correspondents include: Kaestner (Neubabelsburg, Berlin); R Kaischen (Sofia); Dr P Kapitza (Mond Laboratory, Cambridge); Prof Karollis (Leipzig University); Prof P Karrer; Dr JR Katz (Amsterdam); TC Keeley (Clarendon Laboratory); Dr WH Keeson (Leiden University); Dr E Kellermann (Edinburgh University); MJ Kelly (Bell Telephone Laboratory, New York); George E Kimball (MIT); F Kind (Manchester); AJ King (Syracuse and illinois University); Prof C Kittel (University of California); Prof W Klemm (Danzig Langfuhr); Klopstock (Lugano); Knaust; Hans Kolb (Nurenberg); Prof Koeniger (Berlin); Fr. Kornfeld; HH Kraak (Leiden University); Prof HA Kramers (United Nations); Dr H Krekeler; K Krishnan (Calcutta); Dr H Kroger (Leipzig); Prof W Kroll (Breslau); G Kronfeld (University College, Nottingham); Dr HR Kruyt (Utrecht); W Kruger; Dr H Kuhn; W Kuhn (Berlin); Kull and Dr Nicholas Kurti Correspondence with Kurti includes a postcard from Budapest with an illustration of the city drawn by Kurti. c.1924-1956