
Christie denied having made this remark, which had been attributed to her by her second husband Sir Max Mallowan in a news report (9 March 1954); according to Nigel Dennis, "Genteel Queen of Crime: Agatha Christie Puts Her Zest for Life Into Murder", Life, Volume 40, N° 20, 14 May 1956 http://books.google.com/books?id=p0wEAAAAMBAJ&pg=PA102, she was quoting "a witty wife"; Quote Investigator reports on "An Archaeologist Is the Best Husband a Woman Can Have" as of uncertain origin. http://quoteinvestigator.com/2016/07/12/husband/
Disputed
Variant: An archaeologist is the best husband a woman can have. The older she gets the more interested he is in her.