A method of producing an electronic document using a plurality of pieces of physical media having a common position location pattern marked thereupon, comprising the steps of: (i) marking a first piece of the physical media using a digital pen, said pen being arranged to acquire data to enable the determination of the location of a tip thereof upon physical media from the position location pattern marked thereupon; (ii) acquiring data relating to strokes and the location of the strokes of the pen upon the first piece of the physical media sequentially, and storing said data in a memory; (iii) acquiring data relating to strokes and the location of the strokes of the pen upon a second piece of the physical media sequentially, and storing said data in a memory; and (iv) arranging the data stored in steps (ii) and (iii) to form at least one electronic document in which the data relating to the first piece of physical media is distinguishable from the data relating to the second piece of physical media.