Find nearest geographic coordinates

Hi guys,

I've a list of geographic coordinates:

L = [ {{<<"longitude">>,6.1457}, {<<"latitude">>,46.2022}},
      {{<<"longitude">>,2.3387}, {<<"latitude">>,48.8582}},
      ... ]

and a specific coordinate X = {{<<"longitude">>,-73.5848},
{<<"latitude">>,45.4995}}.

Question: how can i find the nearest coordinates to X from L (sorted from
the nearest to the farest)?

/Frank