Whitaker's Almanack is a reference book (first produced in 1868) which is published on an annual basis.
It contains a section dealing with precedence, the order in which dignitaries should be addressed, seated, acknowledged etc. on official occasions.
Virginia Woolf also refers to 'Whitakers Table of Precedency' in her short story, The Mark on the Wall which was published in 1917 in Publication No. 1: Two Stories (the very first publication of the Hogarth Press).