Nadrah, Nadrah. “Test Dimensionality and Conditional Independence of Undergraduate Physics Test Items of National Open University of Nigeria: Perspective from Latent Traits Model (Ltm) Package of R Language”. International Journal of Membrane Science and Technology 10, no. 5 (October 9, 2023): 467-477. Accessed July 3, 2024. https://cosmosscholars.com/phms/index.php/ijmst/article/view/2531.