I want to know the answer to the following question:
When did more madaris begin to form more rapidly?
All the background I'm provided with is that "In central and eastern Islamic lands, the view that the madrasa, as a charitable endowment, will remain under the control of the donor (and their descendent), resulted in a "spurt" of establishment of madaris in the 11th and 12th centuries.". Is that enough to answer the question?