The seven chords of A minor are Am, Bdim, C, Dm, Em, F, G. Each one has a job in the key, and each tends towards particular chords next.
Where a chord tends to go follows Walter Piston’s table of usual root progressions in Harmony (W. W. Norton); see the sources.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.