Thorsten is correct about the GA analysis. I thought I would add in a couple thoughts just in regards to these offline marketing landing pages that will hopefully help. I would recommend in the future not choosing a url of /ad1 or /ad2. I would try to come up with something that is easy to remember for users and has relevance to either the publication or what you are promotion. For example /deal or /offer. Another way to go would be to make something relevant to the publication like /grpress (Grand Rapids Press is a local newspaper where we're at)
The other comment would be to design this page as relevant to the ad, offer or just make it a true landing page and not do the redirection technique. Make this page reference the ad and include a call to action related to what you may have placed in the printed publication.