This octave can also be designated with one uppercase letter (i.e. C) or in the 2nd octave under Acoustical Society of America system (i.e. C2). The MIDI Octave Designation System has two versions, one where note 1 (8.176 Hz) is octave "0" making the Great octave the third octave (i.e. C3), and the other with note 1 (8.176 Hz) at octave "-2" making the Great octave the first octave (i.e. C1).
The indication 8vb (shown below) can be used to represent the same pitches without as many ledger lines.
Play Great Octave Example (MIDI file format)