Solving Sudoku puzzles made easy (part 9)

By now, you should have four cells in rows six and seven which are marked "1,4" (i.e. we had previously established that these cells could be either 1 or 4).
Having entered a four in the bottom-middle box, it's now party time.
The cell marked "1,4" in the bottom-middle box must be a 1.
So the one above that must be a 4.
So the one to the left if that must be a 1.
So the top-middle cell in the bottom-right box must be a 4.
Finish off the bottom-middle box with a 5.
This leaves us 1 and 9 missing from row eight. Do the 9 first and then plug in 1.
Full series here.