M. Gryl, T. Seidler, J. Wojnarska, K. Stadnicka, I. Matulková, I. Němec, and P. Němec. Co-Crystals of 2-Amino-5-Nitropyridine Barbital with Extreme Birefringence and Large Second Harmonic Generation Effect. Chemistry - A European Journal, Wiley, volume 24, issue 35, June 2018.