Grate the rind of lemons and squeeze out the juice. Coat the chicken inside with grated lemon peel and pour out with lemon juice. Place chicken in a non-metallic container, cover with a lid and leave it in the fridge for 2-3 hours. Season chicken with salt and pepper, place it in a baking dish, pour the melted butter it with olive oil and add 1/2 cup water and bake for 20 minutes in a preheated 220 C oven. Reduce oven to 180 C and bake for about 35 minutes. In bowl, combine yogurt, eggs, 5 tbsp water and shake well. Pour over the chicken and bake another 15 minutes or until sauce thickens.