Dedication by Oyler
There are no extra notes required for this puzzle, other than those appearing in The Times, reproduced below:
One possible starting point was: from consideration of 29A, 24D can only be 27. Then 23A is 72, 18D 77, 21A 45 and 7A 231. 22D is 575 and 37D 108. Further deductions can be made, allowing completion of much of the grid. Towards the end, consideration of the letter equivalences allowed determination of the quotation and its author, thus providing feedback for the remaining numbers in the grid to produce the required letters. The full text is “Read Euler, read Euler. He is the master of us all. Laplace.” Euler was born in 1707. Laplace was a renowned French mathematician.