“Effect of Application of Liquid Organic Fertilizer of Pineapple Peel Waste on Growth and Production of Red Lettuce Plants (Lactuca sativa var. Crispa): Pengaruh Aplikasi Pupuk Organik Cair Limbah Kulit Nanas Terhadap Pertumbuhan Dan Produksi Tanaman Selada Merah (Lactuca sativa var. Crispa)” (2023) Procedia of Engineering and Life Science, 4. doi:10.21070/pels.v4i0.1404.