facebook - Get all facebook user profile images of definite size?

Question

I need all the profile pictures of square size. Presently I am able to loop through all the profile pictures but I am unable to get each of those pictures of same size. Since I have a unique id for each picture is there anyway to get that picture with a definite size? Here is the code

   FB.api('/me/albums',   {access_token: token},function(resp) {
                for (var i=0, l=resp.data.length; i<l; i++){
                    var album = resp.data[i];
                        if(album.name=="Profile Pictures"){
                             FB.api(album.id + "/photos", function(response) {
                                for(var j=0;j<response.data.length;j++){
                                    $("#container").append("<li><input type='radio' class='fbimg'><img src='" + response.data[j].picture + "' /></input></li>");    
                                }

                            });

                        }                    
                }
            });