For articles without an author and for this particular project, many of your article titles may be similar or exactly the same because they are likely the saint's name.
If the article titles are exactly the same , then you take the first word of the "article" title and the first word of the italicized title with a comma in between.
"Francis of Assisi, St." Environmental Encyclopedia, Gale, 2015. Biography In Context, http://link.galegroup.com/apps/doc/EJ3018100005/BIC?u=prov94491&sid=BIC&xid=b81b08c3. Accessed 31 May 2018.
"Francis of Assisi, St." Encyclopedia of World Biography, Gale, 1998. Biography In Context, http://link.galegroup.com/apps/doc/K1631002288/BIC?u=prov94491&sid=BIC&xid=0ccfddf2. Accessed 31 May 2018.
("Francis", Environmental).
("Francis", Encyclopedia).
If the article titles begin with the same first word(s), you include include all of the same words + the first word that is different:
"The Life of Saint Francis of Assisi." World Eras, Gale, 2012. Biography In Context, http://link.galegroup.com/apps/doc/K1646400015/BIC?u=prov94491&sid=BIC&xid=12197897. Accessed 31 May 2018.
"The Life of St. Francis." Historic World Leaders,, Gale, 2014. Biography In Context, http://link.galegroup.com/apps/doc/K1616000216/BIC?u=prov94491&sid=BIC&xid=badf7b54. Accessed 31 May 2018.
("The Life of Saint").
("The Life of St.").