diff --git a/docs/phoneme_model.md b/docs/phoneme_model.md
index 6d33eb92..6a74e1d9 100644
--- a/docs/phoneme_model.md
+++ b/docs/phoneme_model.md
@@ -99,6 +99,63 @@ features:
| `app` | approximant | The vocal tract is narrowed at the place of articulation without being turbulant. |
| `vow` | vowel | The phoneme is articulated as a vowel instead of a consonant. |
+## Place of Articulation
+
+The place of articulation is described in terms of an active articulator and
+one or more passive articulators\[9\]. The
+possible places of articulation are:
+
+| Place of Articulation | Feature | Active | Lips | Teeth | Passive |
+|-----------------------|-----------|--------|-------|---------|---------|
+| bilabial | `blb` | `lbl` | `ulp` | | |
+| linguolabial | `lgl` | `lmn` | `ulp` | | |
+| labiodental | `lbd` | `lbl` | | `utt` | |
+| bilabial-labiodental | `bld` | `bld` | `ulp` | `utt` | |
+| interdental | `idt` | `lmn` | | `utt` | |
+| dental | `dnt` | `apc` | | `utt` | |
+| denti-alveolar | `dta` | `lmn` | | `utt` | `alf` |
+| alveolar | `alv` | `lmn` | | | `alf` |
+| apico-alveolar | `apa` | `apc` | | | `alf` |
+| palato-alveolar | `pla` | `lmn` | | | `alb` |
+| apical retroflex | `arf` | `sac` | | | `alb` |
+| retroflex | `rfx` | `apc` | | | `hpl` |
+| alveolo-palatal | `alp` | `dsl` | | | `alb` |
+| palatal | `pal` | `dsl` | | | `hpl` |
+| velar | `vel` | `dsl` | | | `spl` |
+| labio-velar | `lbv` | `dsl` | `ulp` | | `spl` |
+| uvular | `uvl` | `dsl` | | | `uvu` |
+| pharyngeal | `phr` | `rdl` | | | `prx` |
+| epiglotto-pharyngeal | `epp` | `lyx` | | | `prx` |
+| (ary-)epiglottal | `epg` | `lyx` | | | `egs` |
+| glottal | `glt` | `lyx` | | | `gts` |
+
+### Active Articulators
+
+| Feature | Name | Articulator |
+|---------|-----------|-------------------------|
+| `lbl` | labial | lower lip |
+| `lmn` | laminal | tongue blade |
+| `apc` | apical | tongue tip |
+| `sac` | subapical | underside of the tongue |
+| `dsl` | dorsal | tongue body |
+| `rdl` | radical | tongue root |
+| `lyx` | laryngeal | larynx |
+
+### Passive Articulators
+
+| Feature | Articulator |
+|---------|------------------------|
+| `ulp` | upper lip |
+| `utt` | upper teeth |
+| `alf` | alveolar ridge (front) |
+| `alb` | alveolar ridge (back) |
+| `hpl` | hard palate |
+| `spl` | soft palate (velum) |
+| `uvu` | uvular |
+| `prx` | pharynx |
+| `egs` | epiglottis |
+| `gts` | glottis |
+
## Phonation
The phonation features describe the degree to which the glottis (vocal chords) are open or closed.
@@ -136,6 +193,21 @@ The phonation features describe the degree to which the glottis (vocal chords) a
[International Phonetic Alphabet](https://en.wikipedia.org/wiki/International_Phonetic_Alphabet). 2017.
Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).
-5. Wikipedia.
+5. Dunn, R. H.,
+ [Cainteoir Text-to-Speech Phoneme Features](https://raw.githubusercontent.com/rhdunn/cainteoir-engine/master/src/libcainteoir/phoneme/phoneme.cpp). 2013-2015.
+
+6. Wikipedia.
+ [Voiced glottal fricative](https://en.wikipedia.org/wiki/Voiced_glottal_fricative). 2017,
+ Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).
+
+7. Wikipedia.
[Extensions to the International Phonetic Alphabet](https://en.wikipedia.org/wiki/Extensions_to_the_International_Phonetic_Alphabet). 2017,
Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).
+
+8. Wikipedia.
+ [Fortis and lenis](https://en.wikipedia.org/wiki/Fortis_and_lenis). 2017,
+ Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).
+
+9. Wikipedia.
+ [Place of articulation](https://en.wikipedia.org/wiki/Place_of_articulation). 2017,
+ Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).
diff --git a/docs/phonemes.md b/docs/phonemes.md
index 88f5b1c3..8b052bf2 100644
--- a/docs/phonemes.md
+++ b/docs/phonemes.md
@@ -4,6 +4,7 @@
- [Other Symbols](#other-symbols)
- [Gemination](#gemination)
- [Manner of Articulation](#manner-of-articulation)
+ - [Place of Articulation](#place-of-articulation)
- [Voice](#voice)
- [Vowels](#vowels)
- [Diacritics](#diacritics)
@@ -11,9 +12,6 @@
- [Air Flow](#air-flow)
- [Phonation](#phonation)
- [Features](#features)
- - [Place of Articulation](#place-of-articulation)
- - [Active Articulators](#active-articulators)
- - [Passive Articulators](#passive-articulators)
- [Rounding and Labialization](#rounding-and-labialization)
- [Vowel Height](#vowel-height)
- [Vowel Backness](#vowel-backness)
@@ -424,6 +422,30 @@ features:
| `lat` | lateral |
| `sib` | sibilant |
+### Place of Articulation
+
+| Feature | Name |
+|---------|-----------------------|
+| `blb` | bilabial |
+| `lbd` | labiodental |
+| `bld` | bilabial-labiodental |
+| `dnt` | dental |
+| `alv` | alveolar |
+| `pla` | palato-alveolar |
+| `rfx` | retroflex |
+| `alp` | alveolo-palatal |
+| `pal` | palatal |
+| `vel` | velar |
+| `lbv` | labio-velar |
+| `uvl` | uvular |
+| `phr` | pharyngeal |
+| `glt` | glottal |
+
+The `bld` place of articulation is used for `afr` consonants that have a `blb`
+onset and a `lbd` release, e.g. in the German p͡f consonant.
+
+__NOTE:__ The IPA charts make a distinction between pharyngeal and epiglottal
+consonants, but Wikipedia does not. This model uses the Wikipedia descriptions.
### Voice
@@ -498,6 +520,7 @@ above table.
| Feature | Symbol | Name |
|---------|--------|-----------------|
| `lgl` | ◌̼ | linguolabial |
+| `idt` | ◌̪͆ | interdental |
| | ◌̪ | dental |
| `apc` | ◌̺ | apical |
| `lmn` | ◌̻ | laminal |
@@ -539,79 +562,6 @@ equivalent `vls` consonant, the resulting consonant is `vls`, not `slv`.
## Features
-### Place of Articulation
-
-The place of articulation is described in terms of an active articulator and
-one or more passive articulators\[9\]. The
-possible places of articulation are:
-
-| Place of Articulation | Feature | Symbol | Active | Lips | Teeth | Passive |
-|-----------------------|-----------|--------|--------|-------|---------|---------|
-| bilabial | `blb` | | `lbl` | `ulp` | | |
-| linguolabial | `lgl` | ◌̼ | `lmn` | `ulp` | | |
-| labiodental | `lbd` | ◌̪ | `lbl` | | `utt` | |
-| bilabial-labiodental | `bld` | | `bld` | `ulp` | `utt` | |
-| interdental | `idt` | ◌̪͆ | `lmn` | | `utt` | |
-| dental | `dnt` | ◌̪ | `apc` | | `utt` | |
-| denti-alveolar | `dta` | | `lmn` | | `utt` | `alf` |
-| alveolar | `alv` | | `lmn` | | | `alf` |
-| apico-alveolar | `apa` | ◌̺ | `apc` | | | `alf` |
-| palato-alveolar | `pla` | | `lmn` | | | `alb` |
-| apical retroflex | `arf` | | `sac` | | | `alb` |
-| retroflex | `rfx` | ◌̺ | `apc` | | | `hpl` |
-| alveolo-palatal | `alp` | | `dsl` | | | `alb` |
-| palatal | `pal` | | `dsl` | | | `hpl` |
-| velar | `vel` | | `dsl` | | | `spl` |
-| labio-velar | `lbv` | | `dsl` | `ulp` | | `spl` |
-| uvular | `uvl` | | `dsl` | | | `uvu` |
-| pharyngeal | `phr` | | `rdl` | | | `prx` |
-| epiglotto-pharyngeal | `epp` | | `lyx` | | | `prx` |
-| (ary-)epiglottal | `epg` | | `lyx` | | | `egs` |
-| glottal | `glt` | | `lyx` | | | `gts` |
-
-The features for these places of articulation are provided for convenience, and
-to make it easier to describe the IPA consonants. Internally, the active and
-passive articulators are used.
-
-The ◌̪ diacritic is `lbd` when used on `blb` consonants, and `dnt` when used on
-`alv` consonants.
-
-The `bld` place of articulation is used for `afr` consonants that have a `blb`
-onset and a `lbd` release, e.g. in the p͡f consonant.
-
-The `alv` consonant is `lmn` as found in French and Spanish, while `apa` is
-`apc` as found in English, as such ◌̻ (*laminal*) is not needed.
-
-__NOTE:__ The IPA charts make a distinction between pharyngeal and epiglottal
-consonants, but Wikipedia does not. This model uses the Wikipedia descriptions.
-
-#### Active Articulators
-
-| Feature | Name | Articulator |
-|---------|-----------|-------------------------|
-| `lbl` | labial | lower lip |
-| `lmn` | laminal | tongue blade |
-| `apc` | apical | tongue tip |
-| `sac` | subapical | underside of the tongue |
-| `dsl` | dorsal | tongue body |
-| `rdl` | radical | tongue root |
-| `lyx` | laryngeal | larynx |
-
-#### Passive Articulators
-
-| Feature | Articulator |
-|---------|------------------------|
-| `ulp` | upper lip |
-| `utt` | upper teeth |
-| `alf` | alveolar ridge (front) |
-| `alb` | alveolar ridge (back) |
-| `hpl` | hard palate |
-| `spl` | soft palate (velum) |
-| `uvu` | uvular |
-| `prx` | pharynx |
-| `egs` | epiglottis |
-| `gts` | glottis |
-
### Rounding and Labialization
| Feature | Symbol | Name | Rounded | Position |