How comply with GPL open source req in intranet?

I am building an intranet web-application for a for-profit company. The application uses a product that has a GPL license. The company is completely fine with open sourcing the code used by the application and which utilizes the GPL'd product.

The question is, how do we properly comply with this? Is leaving a link on a page in the web application to the source complying? Even if the site is viewable only internally on the company's network?

Thank you.