Bruel & Kjaer - 2203 Documentation
Manual
http://www.download-service-manuals.com/en/manual.php?file=BruelKJAER-9060.pdf
Documentation
http://www.aerc.jp/en/pdf/201204/Sound%20level%20meters%201928%20to%202012.pdf
Applications
http://www.dtic.mil/dtic/tr/fulltext/u2/646025.pdf
http://www.sandv.com/downloads/0808brue.pdf
https://www.tandfonline.com/doi/abs/10.3109/00381797209075559?journalCode=ijap20
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19820014927.pdf
