В оформлении обложки использованы фотографии с
https://pixabay.com/ru/%D0%B7%D0%B5%D0%BC%D0%BB%D1%8F-%D0%BB%D1%83%D0%BD%D0%B0-%D0%BF%D1%80%D0%BE%D1%81%D1%82%D1%80%D0%B0%D0%BD%D1%81%D1%82%D0%B2%D0%BE-%D0%B3%D0%BB%D0%BE%D0%B1%D1%83%D1%81-2822497/
https://pixabay.com/ru/%D1%87%D0%B5%D0%BB%D0%BE%D0%B2%D0%B5%D0%BA-%D0%BE%D1%82%D1%87%D0%B0%D1%8F%D0%BD%D0%B8%D0%B5-%D0%BF%D1%80%D0%BE%D0%B1%D0%BB%D0%B5%D0%BC%D0%B0-65049/
https://pxhere.com/ru/photo/163844; https://inosmi.ru/photo/20121129/202775114_202768955.html
https://pixabay.com/ru/%D1%84%D0%B0%D0%BD%D1%82%D0%B0%D0%B7%D0%B8%D1%8F-%D0%BF%D1%80%D0%BE%D1%81%D1%82%D1%80%D0%B0%D0%BD%D1%81%D1%82%D0%B2%D0%BE-%D0%B3%D0%B0%D0%BB%D0%B0%D0%BA%D1%82%D0%B8%D0%BA%D0%B0-2328442/
по лицензии CC0.