“Super-Symmetry Quantum Factorization Of Radial Schrodinger Equation for the Doubly An-Harmonic Oscillator Via Transformation to Bi-Confluent Heun’s Differential Operators”. Global Journal of Science Frontier Research, vol. 16, no. 18, June 2016, pp. 31-37, https://journalofscience.org/index.php/GJSFR/article/view/.