In academic writing, abbreviations for the following are not commonly accepted.
personal names Charles (not Chas.)
days of the week Monday (not Mon.)
holidays Christmas (not Xmas)
months January, February, March (not Jan., Feb., Mar.)
courses of study political science (not poli. sci.)
divisions of written works chapter, page (not ch., p.)
states and countries Massachusetts (not MA or Mass.)
parts of a business name Adams Lighting Company (not Adams Lighting Co.); Kim and Brothers (not Kim and Bros.)
note: Use abbreviations for units of measurement when they are preceded by numerals (13 cm). Do not abbreviate them when they are used alone. See P9-d.
exception: Abbreviate states and provinces in complete addresses, and always abbreviate DC when used with Washington.