A question in understanding some part of paper of Frobenius

Question

I am learning German, and reading German paper of Frobenius (click here). It is "Verallgemeinerung des Sylow'schen Satzes / G. Frobenius"

I didn't understand few things, and I didn't find the answer through internet. Therefore, I am posting question here. It is not about any mathematical question.

I want to know the meaning of following bold faced terms:

1) Dies Resultat leitet Sylow (a. a. O. S. 588) aus dem Satz ab: [page 1]

2) Gesammtsitzung vom 31. October. [page 2, top]

3) Crelle's Journal Bd. [page 1]

In (1), what is the full form of a. a. O. S. 588? I didn't get this anywhere through internet sources.

Answer 1

These are the translations:

1) 'This result Sylow ( op. cit. p. 588 ) derives from the theorem':

('a.a.O.' = 'am angegebenen Ort') literally translates as 'at the given place'. It references the same source that the preceding bibliographic reference has cited and serves as a shorthand to avoid repetitive references (the bracketing notation - eg. [1], [Sylow69] - is not common across all scientific disciplines or periods)

2) 'General meeting on October 31'

3) 'Crelle's Journal, Vol.'