Penerapan prinsip asas kebebasan berkontrak dalam pembuatan perjanjian pengikatan jual beli satuan rumah susun menurut undang-undang rumah susun nomor 20 tahun 2011 (kasus pelaksanaan PPJB sarusun di Apartemen Casablanca East Residence) = The application of freedom principle contract in making a binding agreement of the sale and purchase apartment units according to the law of apartments number 20 year 2011 (the cases implementation of the a binding of the spa apartment unit at the Casablanca east residence apartemen) / Azwar Apriyadi