В оформлении обложки использованы фотографии по лицензии CC0.
https://pixabay.com/ru/skype-%D0%B6%D0%B5%D0%BD%D1%89%D0%B8%D0%BD%D0%B0-%D0%BA%D0%BE%D0%BC%D0%BF%D1%8C%D1%8E%D1%82%D0%B5%D1%80-%D0%BD%D0%BE%D1%83%D1%82%D0%B1%D1%83%D0%BA-835470/
https://pixabay.com/ru/%D0%BF%D1%83%D1%81%D1%82%D1%8B%D0%BD%D1%8F-%D0%BF%D0%B5%D1%81%D0%BE%D0%BA-%D0%BF%D0%B5%D0%B9%D0%B7%D0%B0%D0%B6-%D1%81%D0%BE%D0%BB%D0%BD%D1%86%D0%B5-%D1%81%D0%B0%D0%BD%D1%81%D0%B5%D1%82-790640/
