“Plasma UFO Conference” in Scientific Study of Unidentified Flying Objects, from: http://www.ncas.org/condon/text/s6chap07.htm#s18. This case is referred to as the RB-47 Radar/Visual case, which occurred over the southern U.S. in July 1957. See: http://www.project1947.com/shg/condon/case05.html; and http://www.ufoevidence.org/cases/case665.htm.
Brad Sparks’ seminal work on the RB-47 case is included in: Jerome Clark, The UFO Encyclopedia: The Phenomenon From The Beginning (Vol. 2) (Detroit: Omnigraphics Books, 1998), 761-790. Available from: http://www.nicap.org/reports/RB47_Sparks_Ency.pdf. Recently, UFO sceptic Tim Printy deconstructed the RB-47 case and published his results in the publication, SUNlite, available from: http://home.comcast.net/~tprinty/UFO/SUNlite4_1.pdf.
In addition, atmospheric physicist, Dr. James McDonald, refutes Klass’ plasma-UFO theory in a presentation to the Canadian Aeronautics and Space Institute, Astronautics Symposium, Montreal, Canada, March 12, 1968. Available from: http://web.archive.org/web/20080907132128/http://ufologie.net/htm/mcdonaldca.htm.