By that time, Olson apparently was still convinced that this phoneme wasn't a labio-dental flap: The bilabial flap is a sound very similar to what is elsewhere called the labiodental flap, but the articulation is slightly different.    From Wordnik.com.  [languagehat.com: NEW PHONETIC SYMBOL!] Reference

An alternation between a bilabial and labiodental sound is comparatively less economic.    From Wordnik.com.  [Concern trolls and the Etruscan bilabial 'f'] Reference

We're probably looking here at the beginning of Olson's preoccupation with the labiodental flap.    From Wordnik.com.  [languagehat.com: NEW PHONETIC SYMBOL!] Reference

” After review of Dr Olson's proposal for the addition of the labiodental flap symbol, the IPA Council voted in favor of the addition.    From Wordnik.com.  [languagehat.com: NEW PHONETIC SYMBOL!] Reference

He begins by explaining the typical communis opinio, making a minor faux-pas by misrepresenting Etruscan f as a labiodental rather than a bilabial fricative.    From Wordnik.com.  [Some observations concerning Woodard's The Ancient Languages of Europe] Reference

For the labiodental flap, several authors state explicitly that the lower lip flaps against the upper teeth see, e.g., Westermann & Ward 1933, Ladefoged 1982.    From Wordnik.com.  [languagehat.com: NEW PHONETIC SYMBOL!] Reference

Dr. Kenneth Olson, SIL's Associate International Linguistics Coordinator, proposed the new labiodental flap symbol, which is technically referred to as “a right hook ‘v'.    From Wordnik.com.  [languagehat.com: NEW PHONETIC SYMBOL!] Reference

The labiodental flap sound is produced by drawing the lower lip back into the mouth well behind the upper teeth and then bringing it forward rapidly, striking the upper teeth briefly in passing.    From Wordnik.com.  [languagehat.com: NEW PHONETIC SYMBOL!] Reference

Frisian has an almost complete set of guttural/velar, dental/alveolar, labial/labiodental consonants voiced and unvoiced plosives, voiced and unvoiced fricatives, nasals and half-vocals, an s, sh, r and l.    From Wordnik.com.  [The etymology of Latin tofus 'tufa' isn't written in stone] Reference

(2000:395) At the same time, Olson and Schrag note that 'the labiodental articulation is an acceptable variant', and they go on to sample some occurences of labial flaps in other African languages (Mangbetu, Linda, Mundang).    From Wordnik.com.  [languagehat.com: NEW PHONETIC SYMBOL!] Reference

Now, this is a matter of detail perhaps but worth noting since p has occasionally eroded to f in Etruscan, particularly next to tautosyllabic u, and this sort of lenition can only rationally happen with a bilabial phoneme, not a labiodental one.    From Wordnik.com.  [Some observations concerning Woodard's The Ancient Languages of Europe] Reference

In eastern Bantu languages, it is commonplace for proto-Bantu bilabial stops voiced and voiceless to change into labiodental fricatives before close high u and/or i, and I do believe – though this needs to be checked – that in some of these languages, these fricatives are in fact bilabials themselves.    From Wordnik.com.  [Concern trolls and the Etruscan bilabial 'f'] Reference

I know you'll all be as excited as I am to learn that the International Phonetic Association has approved the adoption of the first new symbol in twelve years into the International Phonetic Alphabet:The symbol proposed by SIL represents the labiodental flap, a speech sound found in central and southeastern Africa.    From Wordnik.com.  [languagehat.com: NEW PHONETIC SYMBOL!] Reference

Technically, F is an unvoiced labiodental fricative.    From Wordnik.com.  [VERBATIM: The Language Quarterly Vol V No 1] Reference

Of the two strands thus formed, the labial forms the labiodental lamina; while the other, the lingual, is the ridge of cells in connection with which the teeth, both deciduous and permanent, are developed.    From Wordnik.com.  [XI. Splanchnology. 2a. The Mouth] Reference

8. It's not absolutely certain that the /f/ of neighbouring Latin was strictly labiodental.    From Wordnik.com.  [Concern trolls and the Etruscan bilabial 'f'] Reference

'' 'f' '' is a labiodental fricative, air being pushed through the upper teeth and lower lip.    From Wordnik.com.  [Citizendium, the Citizens' Compendium - Recent changes [en]] Reference

If you mean pronouncing /r/ as a labiodental approximant, I don’t know about the 1800s but it is pretty common now in Britain.    From Wordnik.com.  [More on 1880s pronunciation | Linguism | Language Blog] Reference

1 He insists on a labiodental fricative without any explanation further down the page, just in case the reader might assume that it was just a silly accuracy error in IPA notation.    From Wordnik.com.  [Some observations concerning Woodard's The Ancient Languages of Europe] Reference

On a phonemic level, the only intermediary available between bilabial stop /p/ and labiodental fricative /f/ is bilabial fricative /ɸ/ since an intermediary labiodental plosive /p̪/ is rarely if ever used as a phoneme.    From Wordnik.com.  [Concern trolls and the Etruscan bilabial 'f'] Reference