Stegeman GI, Hu H. Refractive Nonlinearity of Linear Symmetric Molecules and Polymers Revisited. Photonics Lett. Pol. [Internet]. 2009 Dec. 31 [cited 2024 Apr. 19];1(4):pp. 148-150. Available from: https://www.photonics.pl/PLP/index.php/letters/article/view/1-50