April 20th is designated by the United Nations as Chinese Language day it seeks to celebrate multilingualism and cultural diversity.
Some great recommended resources are: Chinese Foreign Policy Database from the Wilson Center which provides a marvellous reference source for Chinese foreign policy from 1949 onwards. It includes a timeline and chronology of key events. Thematic sections and biographies. It includes hundreds of full text Chinese and international government documents offering a range of perspectives on events. Mainly 1949-2000. Some are declassified materials.
Chinese Digital Archive 1966-1976 (ANU) More than 400 digitized documents dealing with the Cultural Revolution free online.
National Social Sciences Database China Free database of government-funded Chinese social sciences journals. Coverage varies, but includes in most cases materials post 2012 . Individual registration required.