Changes
Use HTTPS for the generated GND link in order to provide increased privacy and security for users. (It appears that the HTTP URL generates a 301 (Moved Permanently) redirect to an HTTPS version of the URL.)
local function gndLink( id )
return '[httphttps://d-nb.info/gnd/' .. id .. ' ' .. id .. ']' .. getCatForId( 'GND' )
end