Margaret Mead, John Knowles and Maria Katzenbach will speak at The Washington Post's Book and Author Luncheon tomorrow at 12:30 p.m. in the Sheraton Hall of the Sheraton Park Hotel.

Mead will discuss her recently published "Letters From the Field 1925-1975." The anthropologist's collection of personal correspondence to family and friends ranges from letters written when she was 23 and working in Samoa to reports written from the same islands in the post-World War II years. The book also documents her work among American Indians and other Pacific cultures.

The most recent novel by Knowles, best known for "A Separate Peace," is "A Vein of Riches." Set in West Virginia during the coal boom of the early 20th century, "A Vein of Riches" follows the life of a mine-owning family and the problems posed by labor agitation and the rise of competitive energy sources.

Katzenbach's first novel, "The Grab," is set in Georgetown. A woman has just died, and her three daughters fight for her possessions. Katzenbach is the daughter of former Attorney General Nicholas de B. Katzenbach.

Tickets are on sale at $9 each. Call Enid Reque at 223-7969 for further information.