* Emily Post: Author of "Etiquette", first published in 1922, which became a cornerstone of American etiquette and is still widely referenced today.
* Amy Vanderbilt: Author of "Amy Vanderbilt's Complete Book of Etiquette", published in 1952, which offered a comprehensive guide to social graces and became a popular resource for many years.
* Letitia Baldrige: Author of "Letitia Baldrige's Complete Guide to Executive Manners", a classic for business etiquette, published in 1982.
* Judith Martin (Miss Manners): Author of "Miss Manners' Guide to Excruciatingly Correct Behavior", a satirical yet insightful take on etiquette, published in 1982 and still widely popular today.
It's important to note that etiquette is a constantly evolving field, and many other authors have contributed to the body of knowledge.