Dear GSL website maintainers:
in the Extensions/Applications section, you link to QtiPlot.
I would like to draw your attention to the fact that QtiPlot
is open source only in a very superficial sense: the source
package is available for download, but the installation
procedure is broken - and there is good reason to suspect that
this is on purpose since the owner of this one-person project
is trying hard to make money out of it, offering support
contracts. Therefore I feel QtiPlot does not merit implicit
endorsement from your side.
With best regards, Hans Gruber