Source: 1. Generative Adversarial Networks (NIPS 2014), 2. Unsupervised Representation Learning with Deep Convolutional GAN (ICLR 2016), 3. Progressive Growing of GANs for Improved Quality, Stability, and Variation (ICLR 2018), 4. Analyzing and Improving the Image Quality of StyleGAN (CVPR_2020)