Tanggung jawab notaris atas kesalahan dalam pembuatan akta yang menimbulkan kerugian bagi para pihak (studi kasus akta perjanjian dan kuasa yang dibuat di hadapan notaris X di Medan) = Responsibilities of notary on the faultiness which cause losses for parties in notary agreement (a case study on agreement and procuration signed before notary "X" in Medan)