Main sources

netcdf	http://www.unidata.ucar.edu/software/netcdf/
cf convention	http://cf-pcmdi.llnl.gov/
units	http://www.unidata.ucar.edu/software/udunits/udunits-1/index.html

Programming

General programming tutorial	http://www.unidata.ucar.edu/software/netcdf/docs/netcdf-tutorial.html
Matlab	http://mexcdf.sourceforge.net/ (in matlab by default in versions >= 2008b)
Fortran 90	http://www.unidata.ucar.edu/software/netcdf/docs/netcdf-f90/
Fortran 77	http://www.unidata.ucar.edu/software/netcdf/docs/netcdf-f77/
Java	http://www.unidata.ucar.edu/software/netcdf-java/
Python	http://www.pytables.org/moin/PyTables and http://www.scipy.org

nco	http://nco.sourceforge.net/
gdal	http://www.gdal.org/
fwtools	http://fwtools.maptools.org/ (OpenEV, GDAL, MapServer, PROJ.4 and OGDI)
spatial ref	http://spatialreference.org/

From netcdf news group comp.lib.netcdf

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