How to make laravel Blueprints morphs method to add column after a specified coloum

While creating migration scripts I can do something like this

Schema::table('books', function(Blueprint $table)
        {
            $table->string('reference')->after('access');
        });

this will create my reference column after access column. But if I want to use morph how would I do this. I was thinking of doing this

Schema::table('books', function(Blueprint $table)
        {

            $table->morphs('reference')->after('access');
        });

However, this gives me a migration error when I try to run the migration. This is because morphs doesn't have a after method. I am using laravel 5.1. I am not sure how I could have the reference columns after access. Any help or suggestion would be great. Thank you

via Chebli Mohamed