In the paper he mentions that he's been interested in pursuing this problem since 1980. A list of his selected publication is available here: http://www.mathnet

In the paper he mentions that he's been interested in pursuing this problem since 1980. A list of his selected publication is available here: http://www.mathnet.ru/php/person.phtml?personid=29899&option_lang=eng http://www.mathnet.ru/php/person.phtml?personid=29899&option... His paper may contain errors, but he's not a crank.