Pattern is no longer available at original source, however, it can be found at the Wayback Machine.

This is a machine knit pattern suitable for a bulky machine. It is knitted flat in one piece and seamed up the edge. The beauty of this pattern is that the thumb is knitted at the same time as the body of the mitten ie. no need to pick up stitches afterwards and add the thumb. There is also no need to seam the thumb afterwards.