In each section a new overtone melody or 'model' is introduced and repeated several times. Each female voice leads a new section eight times, and each male voice, nine times. Some of the other singers gradually have to transform their own material until they have come into 'identity' with the lead singer of the section by adopting the same tempo, rhythm and dynamics. When the lead singer feels that 'identity' has been reached, he or she makes a gesture to another singer who leads the next section. Each model is a set of rhythmic phonetic patterns, often with actual words used as their basis, such as 'Hallelujah' or 'Saturday'. In 29 of the sections, 'magic names' are called out. These are the names of gods and goddesses from many cultures—Aztec, aboriginal and Ancient Greek, for instance—and have to be incorporated into the character of the model. The erotic and intimate love-poems that are recited were written by Stockhausen 'during amorous days' in 1967.