Bibliography
Frequently Asked Questions About Custom Printing Bags, Brown and Pratt: /custom-printed-bags/faqs/
25 Insane (But True) Facts About Promotional Products, Sage: https://www.sageworld.com/blog/index.php/2015/04/30/25-insane-but-true-facts-about-promotional-products/
Global Advertising Specialties Impressions Study 2016, A cost analysis of promotional products
versus other advertising media, Advertising Specialty Institute:
https://media.asicentral.com/resources/impressions-study-2016.pdf
