Does anyone have a good lime curd recipe?

4 medium limes
100g butter
350g granulated or castor sugar
4 eggs lightly beaten

Grate the lime rind into a basin then add the squeezed juice. Cut the butter into pieces and add it with the sugar. Strain the eggs into the basin. Place over a pan of simmering water then stir until the butter is melted and the sugar has dissolved. Continue to cook, stirring constantly until the curd thickens enough to coat the back of a wooden spoon. Do not overcook or the eggs may curdle. Pour into steralised warm jars then cover with a wax disc and cellophane as for jam. Keeps for 1 month or 3 months refrigerated.