nr. 948 - Daily League Sudoku - Quadruple Sudoku

This is a familiar sudoku variant. I think it is one of the easiest where there is no given numbers.


If you want to solve this sudoku online you can do it tomorrow at SudokuCup.

Rules for Quadruple Sudoku:
Follow classic sudoku rules. At some intersections of two crossing grid lines, a set of four numbers is given. These numbers must be placed in the four adjacent cells.