Help me with the sentence please..

[nuni]

Please help me with this confusing sentence.. Can you explain me the meaning of it? Perhaps you can make the sentence into two/three smaller parts.


"He could tell of the top of his head on which page in which obscure Russian journal theorem similar to the one you were working on was proved in 1922."


Thank you..

[TheStephen]

"He knew the volume and page number for that theorem. It's similar to the one you had helped prove in 1922."

Does that help you?