code: public static Point2d WSG84_L4(double lambda, double phi) {
  		final Point2d ntfLambdaPhi = WSG84_NTFLamdaPhi(lambda, phi);
  		return NTFLambdaPhi_NTFLambert(
  				ntfLambdaPhi.getX(), ntfLambdaPhi.getY(),
  				LAMBERT_4_N,
  				LAMBERT_4_C,
  				LAMBERT_4_XS,
  				LAMBERT_4_YS);
  	}
docs: This function convert WSG84 GPS coordinate to France Lambert IV coordinate.
  
  @param lambda  in degrees.
  @param phi  in degrees.
  @return the France Lambert IV coordinates.