Matthew Bennet has a good article titled “La Régle du Temple as a Military Manual or How to Deliver a Cavalry Charge” which is a good place to start. By extension, the Rule of the Templar’s has information about how the Templars organized themselves in battle. If you read between the lines a bit you can get a pretty good idea how knights might be used in battle.

“Victory in the East” by John France and “Crusading Warfare” by R.C. Smail can also offer some insight into the way heavy horsemen were used in the crusading period.

Andrew Ayton’s “Knights and Warhorses” is more about the social development of the English military class, but it covers some ground related to the role of knights and cavalry in warfare.

There are many more titles you could explore, but those are the ones that immediately spring to mind.

I hope that helps.

Edit:

I just remembered this article by Michael Harbinson “The Lance in the Fifteenth Century: How French Cavalry Overcame the English Defensive System in the Latter Part of the Hundred Years War”. If you can get your hands in it, I recall it being very informative about medieval cavalry warfare.

There is also an interesting article titled “Couched Lance and Mounted Shock Combat in the East: The Georgian Experience” that discusses mounted shock combat from an eastern Christian perspective but which might be interesting for a general idea about how mounted shock combat worked.