Article on "No Referer" Pages
The Dreaded "No Referrer"
If you're selling big, bulky items that cost in the hundreds or
thousands of dollars -- especially if it's a business-to-business
transaction you probably know it's impossible to accurately track
every sale or lead back to the initial online search that ultimately
generated the sale. We can discuss the obvious reasons in the
technology and user behavior: cookie deletion, latent purchases,
difficulty of tracking phone sales, users with multiple computers, etc.