Kekuatan hukum jual beli tanah melalui surat pernyataan penyerahan hak atas tanah (analisis Putusan Mahkamah Agung Nomor 134 PK/PDT/2016) = The legality of land sale and purchase agreement using statement letter regarding relinquishment of land review of supreme court stipulation No 134 PK/PDT/2016 / Zulfikar Raharjo