31 it is also important that the data page 27 can be produced with a comparatively thin wall thickness d in its entire region in particular by means of lamination fig9 shows a booklet in particular a passport according to a variant the booklet 33 has a cover 34 which is folded as usual at a spine 35 and into which a plurality of sheets 36 are bound in a known manner the booklet 33 additionally has a data page 37 which has a flexible layer 38 having a fold 39 which runs parallel to the spine 35 arranged between two parts 38 a and 38 b of the layer 38 is a data carrier 41 which can be a plastic film or else an injection moulded part embedded in the data carrier 41 is an electronic component and in particular an electronic chip 42 which is connected to the antenna 43 indicated in fig1 the chip 42 contains data which can be read without contact the chip 42 can also have a contact interface the antenna 43 can also be located completely in the data carrier 27 also conceivable is the integration of a dual chip module into the data carrier 27 which can be addressed by a contact area and without contact via an antenna a chip 42 is also possible in the data carriers according to fig1 5 and 8 the layer 41 preferably also contains data that can be detected visually and which for example are applied in a known manner by means of a laser the flexible layer 38 is firmly connected to the data carrier.