http://www.psych.usyd.edu.au/staff/alexh/teaching/auditoryTute_2014/ http://www.psych.usyd.edu.au/staff/alexh/teaching/auditoryTu... http://www.roger-russell.c

http://www.psych.usyd.edu.au/staff/alexh/teaching/auditoryTute_2014/ http://www.psych.usyd.edu.au/staff/alexh/teaching/auditoryTu... http://www.roger-russell.com/hearing/hearing.htm http://www.roger-russell.com/hearing/hearing.htm http://personal.cityu.edu.hk/~bsapplec/frequenc.htm http://personal.cityu.edu.hk/~bsapplec/frequenc.htm https://www.researchgate.net/publication/261767650_Extended_high-frequency_9-20_kHz_audiometry_reference_thresholds_in_645_healthy_subjects https://www.researchgate.net/publication/261767650_Extended_... (table 2)