To reference the WAVEWATCH III manual version 6.07, please use the
following citation: 

The WAVEWATCH III® Development Group (WW3DG), 2019: User manual and system documentation of  WAVEWATCH III® version 6.07. Tech. Note 333, NOAA/NWS/NCEP/MMAB, College Park, MD, USA, 326 pp. + Appendices. 

We recomend shortening the full author name "The WAVEWATCH III 
Development Group (WW3DG)" to "WW3DG" within the text of a document.

For latex users, the bibtex entry is: 

@TECHREPORT{ww3man2019,
  AUTHOR      = "{The WAVEWATCH III$\:$\textsuperscript{\textregistered} Development Group (WW3DG)}",
  YEAR        = "2019",
  TITLE       = "User manual and system documentation of {WAVEWATCH III}~\textsuperscript{\textregistered} version 6.07",
  INSTITUTION = "NOAA/NWS/NCEP/MMAB",
  ADDRESS     = "College Park, MD, USA",
  TYPE        = "Tech. Note",
  NUMBER      = "333",
  NOTE        = "465 pp. + Appendices" }

For bibtex, to use a 'short author' name of "WW3DG" instead of the full 
author name "The WAVEWATCH III Development Group (WW3DG)" add in 
the preamble: 
\usepackage{natbib}
\defcitealias{ww3man2019}{WW3DG}

Then to use the short name, within your document use \citetalias or 
\citepalias instead of \cite, \citet, or \citep.  Note that the alias 
does not include the year. To include the year, use 
\citepalias[2019]{ww3man2019} which will appear as (WW3DG, 2019) or 
\citetalias{ww3man2019} \citeyearpar{ww3man2019} which will appear
as WW3DG (2019).

For any questions, contact the WAVEWATCH III code manager at
NCEP.List.WAVEWATCH@noaa.gov