The corrections are to step 3 and figures 1 and 3, all of which pertain to measurement and to the number of folds that you need to make. Here is the problem: when you use a concertina with longstitch, Coptic, or sewn-on-tapes books, you nest the signatures (little booklets of pages) into the valley folds of the concertina, as shown in figure 3. But when you use a concertina in constructing either of the Australian reversed piano hinge books, you slide the mountain folds of the concertina into slits in the center folds of the signatures, which calls for a slightly different number of folds. (See figure 4 below)
The change you must make to step 3 is to add the following to the end of the step: "For Australian reversed piano hinge books, use this formula: Make two scores for each folio."
There is also a small measurement correction to make underneath figure 1. You should write, under figure 1, "For Australian reversed piano hinge, measure 2 inches for each signature. Ex. for 5 signatures, measure 2 x 5 = 10 inches."
