A. Apriyanto, M. Sholeh, and W. Setiawardani, “Management of Teacher Discipline Development Through a Web-Based QR Code Attendance System with WhatsApp E-Notifications at SMK (Vocational School) Nahdlatul Ulama (NU) Kaplongan Indramayu”, J.Gen.Educ.Humanit., vol. 4, no. 4, pp. 1949–1962, Nov. 2025.