[1] In an effort to prevent the language from being lost, a group of researchers from the University of Hawaii interviewed the few remaining Tillamook-speakers and created a 120-page dictionary.

The acoustic effect of labialization is created entirely inside the mouth by cupping the tongue (sulcalization).

These contrast and oppose otherwise very similar segments having ɛ or ɪ coloring—the "unrounded" consonants.

/w/ is also formed with this internal rounding instead of true labialization, making it akin to [ɰ].

So are vowel sounds formerly written as /o/ or /u/, which are best characterized as the diphthong /əɰ/ with increasing internal rounding.