Muhammad Alwi et al. 2021. Classification of Book Collections Based on DDC 23 Using Text Mining Algorithm at UNIDA Gontor Library: Klasifikasi Koleksi Buku Berbasis DDC 23 Menggunakan Algoritma Teks Mining di Perpustakaan UNIDA Gontor. Procedia of Engineering and Life Science. 2, (Nov. 2021). DOI:https://doi.org/10.21070/pels.v2i0.1164.