Tanggung Jawab Pejabat Pembuat Akta Tanah Sebagai Pejabat Umum Terhadap Pembatalan Akta Jual Beli Akibat Perbuatan Melawan Hukum (Studi Kasus Putusan Peninjauan Kembali Mahkamah Agung RI Nomor 645 PK/Pdt/2020) = The responsibility of the land deed official as a public official for the cancellation of the sale and purchase deed due to an unlawful act (Case Study of the Supreme Court Review Decision of the Republic of Indonesia Number 645 PK/Pdt/2020)