Vang, T., Nguyen, D., Le, T., Le, L., Pham, A., Le, T., Tran, H. and Pham, T. 2023. Enrichment of anammox sludge by using an Internal Circulation Reactor innoculated with anaerobic granular sludge and old landfill leachate. Science & Technology Development Journal: Science of the Earth & Environment. 7, 1 (Jun. 2023), 683-690. DOI:https://doi.org/https://doi.org/10.32508/stdjsee.v7i1.732.