Australia: Airmail labels 2

Here are some old airmail labels from Australia.

Year: 5.1930, Gummed. Günter Mair's catalogue no: - AUS-A-1a, rouletted, sheets of 20(2x10), white or
cream gum, blue or dark blue/white, 3***

Year:1933, Gummed. Günter Mair's catalogue no: - AUS-A-2, rouletted, sheets of 20(2x10), lettering
modified ("R"), black-blue or dark ultramarine or dark blue or violet-blue or blue/white, 3***

Year: 1941, Gummed. Günter Mair's catalogue no: - AUS-A-5c, rouletted, sheets of 30(3x10), 
"BY AIR MAIL": 28mm, "PAR AVION": 22mm, dark blue or dark ultramarine/white, 3***

Year: 1941, Gummed. Günter Mair's catalogue no: - AUS-A-5f, rouletted, sheets of 30(3x10), 
"BY AIR MAIL": 28mm, "PAR AVION": 22mm, blue or dark blue/light greenish blue, 3***