I simply want to know which it was for future reference.

Please mark down the date and time for future reference.

Offer to provide them with a future reference of your own, if needed.

I need to note where it is, as a matter of future reference.

Better to do it on your two feet, then you'll know where everything is for future reference.

Maybe you should have taken some notes for future reference.

If so, please take note of it for future reference.

I would therefore like to take this opportunity to say a few things for future reference.

I just wanted to raise a point for future reference.

The point I have made is for future reference, so to speak.