Https://ppf.ucsf.edu/sites/ppf.ucsf.edu/files/webform/complete-list-of-copyright-desktop-service-usa-contact-numbers-a-step-by-step-guide.pdf https://ppf.ucsf.edu/sites/ppf.ucsf.edu/files/webform/complete-list-of-copyright-desktop-service-usa-contact-numbers-a-step-by-step-guide.pdf