Verticle lines indicate 10 second time intervals.
Dynamics have to be neutral, neither too weak or too strong, but always well balanced.
Breathings must, if necessary, be made at the time when the two voices meet on a same pitch - but one of the two voices should keep on sounding when the other is having a breathing/interruption/time. It will be better to breathe as little as possible during the piece. Consequently circular breathing is obligatory.
