Answered By: Colleen Bryant Last Updated: Aug 08, 2016 Views: 12
You should find the guide Finding Periodical Articles and Book Reviews on Latin America useful. Like all our guides, it has direct links to online resources. Try searching using "sulpher," "sulphur," and "sulfer."
There is some archival material in Baker: http://www.library.hbs.edu/hc/lehman/company.html?company=pan_american_sulphur_company
This Google Book has some information: http://books.google.com/books?id=6faNAQAAQBAJ&lpg=PA264&ots=n9cWi13EnG&dq=pan%20american%20sulphur%20company%20history&pg=PA264#v=onepage&q=pan%20american%20sulphur%20company%20history&f=false