The Long-term structural effect of Coronal index solar activity on the ENSO and QBO Time series data using Fractal Dimension. Punjab Univ. J. Math. [Internet]. 2025 May 13 [cited 2025 Jun. 29];53(2):147-61. Available from: https://pujm.pu.edu.pk/index.php/pujm/article/view/258