General Reference
Encyclopedias
The Canadian Encyclopedia
https://thecanadianencyclopedia.ca/en
International Encyclopedia of the First World War
Dictionaries - General
Cambridge Dictionary
https://dictionary.cambridge.org/
Dictionary.com
Merriam-Webster Dictionary
https://www.merriam-webster.com/
Oxford Learner’s Dictionaries
Dictionaries - Special
Dictionary of Canadian Biography
Dictionary of Canadianisms on Historical Principles
Thesauruses
Thesaurus.com
Other
CIA World Factbook
https://www.cia.gov/library/publications/the-world-factbook/
"The World Factbook [is an American resource that] provides information on the history, people and society, government, economy, energy, geography, communications, transportation, military, and transnational issues for 267 world entities. The Reference tab includes: a variety of world, regional, country, ocean, and time zone maps; Flags of the World; and a Country Comparison function that ranks the country information and data in more than 75 Factbook fields." - From the website's main page.
​
InfoPlease
"Infoplease is a reference and learning site, combining the contents of an encyclopedia, a dictionary, an atlas and several almanacs loaded with statistics, facts, and historical records." - From the website's About page.