region 1 must be external and the region 3 internal the surface shown in fig1 is that which is to be compiled or printed on the reference numerals 9a 9b 9c indicate by way of example some parts of the compilation included in the region 3 a further compilation part 9e is located in the region 1 and represents the postal address of the receiver fig2 shows the rear surface of the form in which the parts 9a 9b 9c 9e of the compilation have been shown by dashed lines being visible only 34 by transparency 34 the rear surface of the form rests on a backing plate while the printing or compilation is taking place on the front surface by a suitable system such as a laser printer in compilation machines the continuous web n of forms fig2 passes by sliding with intermittent movement on the backing plate the dimension of which is indicated in fig2 by dp this dimension is limited and does not substantially exceed the longitudinal dimension of region 3 of the form the region 3 can be reduced in length and possibly also in width not only by the absence of paper material but also possibly by window apertures in order to remain functionally equivalent after compiling the form and separating it from the continuous web n the form is folded firstly along the line 5 so that the form assumes the state shown in fig3 in a second stage the form must.