Hello, I think this question bothers everybody who doesn't have articles in his/her mother tongue: we learn that all countable nouns must have an article before them, but I've run across many examples where there are none (and by this rule, should be). They are not just "fixed phrases" (that being the possible explanation)
One example from the leaflet I am holding in my hands right now:
"More about excursions find out on internet page
www.....blah"
Shouldn't be an article there, in front of "internet page" (thanks a lot in advance, guys
!)