Chacko, Anusha, and Shanty Chacko. “Efficient and Robust Medical Image Watermarking Based on Optimal Subband Tree Structuring and Discrete Fractional Fourier Transform”. Computer Assisted Methods in Engineering and Science, vol. 30, no. 4, Oct. 2023, pp. 557–581, https://doi.org/10.24423/cames.547.