I have recently learnt about Augmented 6th chords. The examples in a music theory workbook had this chord written on the flattened submediant (6th degree of the scale). There was a small note in the book about this chord being written on the flattened supertonic (2nd degree of the scale) as well, but there were no examples.
How do you write an augmented 6th chord on the flattened supertonic, with examples? Is it different than writing the chord on the flattened submediant?