Lip whistling remains understudied despite decades of acoustic research

Evidence

A lip whistle may not be one of the most perplexing problems in acoustics anymore, but it is remarkable how little attention it has gotten. On the Internet, the information gap has been filled with misinformation. — Eric J. Heller, Why You Hear What You Hear- An…, 1320

Categorization

• QUESTION: An under-researched corner of acoustics; would be worth investigating the current state of lip-whistle scientific literature.
• SEED: Article angle: the strangest under-solved problem in acoustics is whistling with your mouth.