Are the missed prayers valid despite being ignorant of the supplication for making them up?

It is presumed that the questioner has been remiss in expediting the performance of missed prayers. It is obligatory for her to pray each day as many of the missed prayers as she can, in addition to the five current obligatory prayers, at any time of the day or night, provided that this does not cause harm to her body or disrupt her livelihood. She should continue to do so until she has made up what she owes, if she knows their number. If she does not know their number, she should make up what she believes is sufficient to fulfill the obligation. There is no specific supplication to be recited when making up missed prayers.