Rahaman, Md Dalilur, Hideo Kaiju, and Akira Ishibashi. 2013. “Ultra-High Cleanliness of ISO Class Minus 2 Realized by Clean-Unit System Platform for Integrating the Bottom-up and Top-down Systems”. Dhaka University Journal of Science 61 (2):157-60. https://doi.org/10.3329/dujs.v61i2.17063.