Pandey, R., Shukla, C., Shukla, A., Upadhyay, A. and Singh, A. K. (2023) “A new approach on approximate controllability of Sobolev-type Hilfer fractional differential equations”, An International Journal of Optimization and Control: Theories & Applications (IJOCTA), 13(1), pp. 130–138. doi: 10.11121/ijocta.2023.1256.