[Preface] "Ramon y Cajal, an appreciation," In Neuron Theory or Reticular Theory? Objective Evidence of the Anatomical Unity of Nerve Cells, trans. Rev. Dr. M. Ubeda Purkiss & Dr. C.A. Fox (Madrid: Institute "Ramón y Cajal", 1954.) ix. / Wilder Graves Penfield (book by Ramón y Cajal)
