The First Presidency, in a letter from March 1983, teaches that books written by a General Authority is not to be considered a Church publication or necessarily represents official Latter-day Saint teaching.
First Presidency Letterhead, March 22, 1983, repr., Dennis B. Horne, Determining Doctrine: A Reference Guide for Evaluating Doctrinal Truth (Salt Lake City: Eborn Books, 2005), 29
First Presidency Letterhead
March 22, 1983
To All General Authorities
Dear Brethren:
At a meeting of the Council of the First Presidency and Quorum of the Twelve held on Thursday, March 17, 1983, it was decided that hereafter when a General Authority writes a book for publication, the preface of the book should contain a statement embodying the points or concepts contained in the following statement:
The author wishes to make it clear that the opinions and views expressed in this publication are those for which he and he alone is responsible. This is not a Church publication and has not been written under assignment of or at the request of the First Presidency or the Quorum of the Twelve Apostles.
Therefore, the views expressed in this book do not represent the official position of The Church of Jesus Christ of Latter-day Saints.
It is expected that the author will phrase the statement in the preface in his own language, but such a statement should, as indicated, embody all of the elements contained in the above quoted statement.
Sincerely, your brethren,
Spencer W. Kimball
Marion G. Romney
Gordon B. Hinckley
The First Presidency