@thesis{thesis,
		author={Jatnika  Hendra and Pratama  Demo Wahyu and Rifai  M Farid},
		title ={Aplikasi Data Pembelian Gas liquefied Petroleum Gas Menggunakan Teknologi QR Code Berbasis Android},
		year={2019},
		url={http://156.67.221.169/4375/},
		abstract={Data processing using applications in the trade recording process can make a major contribution to the effectiveness, efficiency and facilitate entrepreneurs in processing sales, purchasing and inventory data. However, at this time there are still many sellers who do the recording / bookkeeping of buying and selling transactions manually, one of which is the sale of LPG Gas at Triple D base, which is still buying and selling LPG Gas by manually recording the Family Card to collect data on residents who will buy LPG gas. The researcher intends to solve this problem by making an application for buying and selling transactions by creating a QR Code for each family card using ROT13 to encrypt the data to be scanned. This method can be applied so that purchases and sales at the Triple D LPG gas base become more effective and efficient and minimize errors in bookkeeping transactions}
		}