Lim, Alex Jun Xiong, Michael Boon Chong Khoo, Wai Chung Yeong, and Abdul Haq. 2019. “A RUN SUM S CHART WITH TWO SAMPLING INTERVALS”. International Journal of Industrial Engineering: Theory, Applications and Practice 26 (4). https://doi.org/10.23055/ijietap.2019.26.4.4272.