docs/research/articulatory-vocal-tract-sources.md cites what the tract design takes from Story, Pink Trombone, VocalTractLab,
Maeda, Kelly-Lochbaum, nasal coupling and LF, with what could not be retrieved. The CSV is Story 2008 Table I (11 vowels, 44
sections). burg_formants.py (Burg LPC on a WAV) and tube_formants.py (frequency-domain tube chain on an area function) share no
code with the ladder. Unheard.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
