These bags were made from Burda Style Charlie Bag pattern which can be found here for free.
I love free patterns almost as much as I like
"keeping it Green"
Of course I've made some modifications to the pattern, like the box bottom. For the box bottom, I just cut out a 2 1/2" square from each corner, pin together, matching side and bottom seams, lay flat and sew across the diagonal and you get a box. I find this method to be the easiest and most accurate. Lined bags are fun because they add a contrasting fabric to make them look more stylish and it makes them stronger.