By Sobol, Donald J.. New York : Four Winds, 1980 . 72 p. : 0590075624 :
]]>By Sobol, Donald J.,. New York : Puffin Books/Penguin Group (USA), 2010 . 84 p. : 20 cm.. 9780142419335 | 9780606231503
Place Hold on Encyclopedia Brown and the case of the secret UFOs /
]]>By Sobol, Donald J.,. New York : Puffin Books/Penguin Group (USA), 2009 . 87 p. : 20 cm.. 9780142416884
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