LAIM, deuxieme partie

(https://www.cia.gov/library/publications/the-world-factbook/geos/ar.html)
This is the CIA world factbook entry on Argentina, which includes a small overview of the history/independence of the country, as well as information about Argentina's current political situation.

(http://www.britannica.com/eb/article-33071/Argentina)
This is the Encyclopedia Britannica article on Argentinian independence. It is very clear-cut and understandeable, and presents a wealth of information on the topic. The article on Argentinean history as a whole is very extensive, even spanning back to the era of the Inca.