Reference
Jazz Chord Symbols: Seventh Chords
Dominant seventh chords
We add a 7 to the letter:
With a suspended fourth:
Major seventh chords
We add Maj7, 
7 o :
Minor seventh chords
We add min7, m7 or -7:
Diminished seventh chord
We add dim7 or o7:
Half-diminished seventh chord
We add 
7, o m7(b5):
Inversions
As with the triads, to indicate an inversion, we add a slash and specify the note that should be played in the bass:
See also: Triads, Ninth Chords, Other Extensions
