Aqualung invention

The company:

European regulators – historical review:

Mechanism of scuba diving regulator in Wikipedia:

There is probably no more comprehensive source of knowledge than PADI Encyclopedia of Recreational Diving, chapter 3 from that source:

US patent

U2485039 patent by Émile Gagnan (1900 – 1984) and Jacques-Yves Cousteau (1910-1997). Gagnan worked earlier for liquid air company in France and Canada.

Z książki W oceanie życia Yves Paccaleta po polsku:

Aparat do nurkowania swobodnego. R7 Paccalet