As he said earlier, you had better check your computer or ISP. I just validated that his first three links and all those I checked (4) up to about #20 worked.
Co-evolution of ligand-receptor pairs in the vasopressin/oxytocin superfamily of bioactive peptides
Co-evolution of ligand-receptor pairs in the vasopressin/oxytocin superfamily of bioactive peptides
There's 3 in a row for you to try to click on in his list.
I certainly hope your science facts aren't based on such scanty trials. He had over 50 sites listed, you verified 4, and you tell me I should check my computer? Do you really think that is a good enough sampling to suggest that I was mistaken?
Why do you feel so compelled to evangelize on the subject of evolution?