If your article is not available at Collins Library, you've got another option to getting it. Use ILLiad, our interlibrary loan service.
You'll need to set up an account the first time you use it and log in subsequently.
Once you have an account, either go directly to ILLiad and manually enter the information, or, if you're using a database, look for a shortcut link to automatically fill out the form, like this:
Allow at least a week for the article to come. If your article is delivered in electronic format, you'll receive an email with a link to follow as soon as it's arrived. If it's delivered in paper, you'll receive it right in your campus mailbox.
For topics related to the Mexican-American borderlands, the following databases are most likely to be useful.
This combined search box covers world history, including the United States and Canada, from 1450 to the present. You may wish to search both databases because border history can be found in each, depending on the focus of the article.