Randall Smith Matthew Self Peter Cheeseman Estimating uncertain spatial relationships in robotics. 435-461 1986 conf/uai/1986 UAI http://uai.sis.pitt.edu/displayArticleDetails.jsp?mmnu=1&smnu=2&article_id=1799&proceeding_id=1002 db/conf/uai/uai1986.html#SmithSC86