Sources

Works Cited

Mariani, Gael. "Henrietta Leavitt – Celebrating the Forgotten Astronomer | AAVSO." AAVSO. N.p., n.d. Web. 20 Feb. 2015. <http://www.aavso.org/henrietta-leavitt-%E2%80%93-celebrating-forgotten-astronomer>.

"1912: Henrietta Leavitt Discovers the Distance Key." 1912: Henrietta Leavitt Discovers the Distance Key. Carnegie Institution for Science, n.d. Web. 20 Feb. 2015. <https://cosmology.carnegiescience.edu/timeline/1912>.

PBS. PBS, n.d. Web. 20 Feb. 2015. <http://www.pbs.org/wgbh/aso/databank/entries/baleav.html>.