Alkaline earthides based on 15-crown-5 ether with remarkable NLO responseAnnum Ahsan, Sehrish Sarfaraz, Mazhar Amjad Gilani, Tariq Mahmood, Zaheer Ahmad and Khurshid AyubEur. Phys. J. Plus, 137 10 (2022) 1149DOI: https://doi.org/10.1140/epjp/s13360-022-03308-z