Very fine, these fittings are sold in lengths of up to three meters and are particularly discreet. Hence their interest...
Position the dimensioned hinge on the door and cabinet jamb to locate the screws. Pre-drill with a wick of Ø 2mm.
Place the hinge on the two panels and screw it with 3mm countersunk wood screws. Avoid forcing not to twist the hinge.
Once in place, the axis of rotation is at the angle between the two panels. In the open position, the hinge will be completely invisible.