However, Heinlein's authorized biographer has said that he looked into the matter at the suggestion of Scientologists but found nothing to corroborate claims that Heinlein had been involved, and his biography of Heinlein makes no mention of the matter. The Church of Scientology says Hubbard quit the Navy because it "attempted to monopolize all his researches and force him to work on a project 'to make man more suggestible' and when he was unwilling, tried to blackmail him by ordering him back to active duty to perform this function. Having many friends he was able to instantly resign from the Navy and escape this trap." The Navy said in a statement in 1980: "There is no evidence on record of an attempt to recall him to active duty." Following Hubbard's death, Bridge Publications published several stand-alone biographical accounts of his life. Marco Frenschkowski notes that "non-Scientologist readers immediately recognize some parts of Hubbard's life are here systematically left out: no information whatsoever is given about his private life (his marriages, divorces, children), his legal affairs and so on." The Church maintains an extensive website presenting the official version of Hubbard's life. It also owns a number of properties dedicated to Hubbard including the Los Angeles-based L. Ron Hubbard Life Exhibition (a presentation of Hubbard's life), the Author Services Center (a presentation of Hubbard's writings), and the L. Ron Hubbard House in Washington, D.C. In late 2012, Bridge published a comprehensive official biography of Hubbard, titled "The L. Ron Hubbard Series: A Biographical Encyclopedia", written primarily by Dan Sherman, the official Hubbard biographer at the time. This most recent official Church of Scientology biography of Hubbard is a 17 volume series, with each volume focusing on a different aspect of Hubbard's life, including his music, photography, geographic exploration, humanitarian work, and nautical career. It is advertised as a "Biographic Encyclopedia" and is primarily authored by the official biographer, Dan Sherman. During his lifetime, a number of brief biographical sketches were also published in his Scientology books. The Church of Scientology issued "the only authorized LRH Biography" in October 1977 (it has since been followed by the Sherman "Biographic Encyclopedia"). His life was illustrated in print in "What Is Scientology?", a glossy publication published in 1978 with paintings of Hubbard's life contributed by his son Arthur. According to the Church of Scientology, Hubbard produced some 65 million words on Dianetics and Scientology, contained in about 500,000 pages of written material, 3,000 recorded lectures and 100 films.