What would "Disintegrant", "Ammonium", or the units of measure "glass" or "gl" mean in a non-American book?
"Ammonium" is probably "baker's ammonia" or "ammonium carbonate" -- this is an old-school leavening agent, which has mostly been replaced with baking soda &amp; baking powder in modern cooking.

A "disintegrant" is the opposite of a binder. Without context, knowing what it is specifically talking about is hard to say. In pharmacology, a disintegrant is used in oral tablets to make them rapidly break up when they get wet. Most "chewable" oral tablet medicines have a disintigrant to help them quickly break up when you put it in your mouth.

Edit: Based on the example recipe that you added, I'm going to guess that it's also reference to some kind of leavening agent. Whether it's intended to be baking powder, baking soda, or is also a reference to baker's ammonia, I'm not sure. Seems like it would be necessary to experiment a little bit to determine--but I think it's safe to say it's probably one of those leavening agents. 

I presume that "gl" is an abbreviation for "glass" and both refer to the same unit. This other question indicates this is a common Russian unit of measure (is your cookbook Russian?). There is no accepted answer on that question, but the answers there all indicate that it is somewhere between 200ml and 1 cup.