Update README.md

README.md

@@ -110,7 +110,7 @@ Input parameters for the spherical atmosphere models (all but the first):
 - xc - CO2 density              [ppm]
 - lat - Latitude                [deg]
 - h - Height above sea level    [m]
-- l - Wavelength(s)             [um]
+- l - Wavelength(s)             [μm]
 - z - Zenith angle              [deg]
 
 An example - To calculate the atmospheric refraction we set up a `refraction()` object. This requires the latitude and altitude of the observer. The atmospheric dispersion is calculated similarly, but by exchanging the `refraction()` object by a `dispersion()` object and parsing two refractive indices into the `cassini()` function.
@@ -195,6 +195,7 @@ Included are
 | Bonsch & Potulski (1998) | `BonschPotulski()` | Allows for any temperature, pressure, humidity and CO2 density. |
 | Birch & Downs (1994) | `BirchDowns()` | Only at standard atmosphere. Function requires wavelength only. |
 | Peck & Reeder (1972) | `PeckReeder()` | Only at standard atmosphere. Function requires wavelength only. |
+| Mathar (2006) | `Mathar()` | Allows for temperature, pressure and humidity specification. Works best at wavelengths above 1.4 μm. |
 | Hohenkerk & Sinclair (1985) | `HohenkerkAndSinclair()` | Based on Barrell & Sears equation. Generally, gives slightly larger values.|
 | Hohenkerk & Sinclair (1985) | `slalib()` | Uses pySLALIB to retrieve the refractive index at standard atmospheric conditions.|
 
@@ -226,6 +227,7 @@ Presently, several observatories are known. These can all be found in the `obser
 | Roque de los Muchachos Observatory (La Palma) | `LA_PALMA`        | GTC, INT, WHT, NOT, and others.               |
 | La Silla Observatory                          | `LA_SILLA`        | ESO 3.6m telescope, NTG, BlackGEM and others. | 
 | Las Campanas Observatory                      | `LAS_CAMPANAS`    | Site of the future GMT.                       |
+| Mauna Kea Observatory (Hawaii)                | `MAUNA_KEA`       | Location of Keck, Subaru, Gemini North and others.|
 
 ## Other