Encyclopedia Britannica - History of Modern Theatre
https://www.britannica.com/art/theater-building/The-evolution-of-modern-theatrical-production
This section of the Encyclopedia Britannica entry on theatre provides a great deal of relevant information about theatrical Naturalism and other forms of modern theatre.
Website of the Virtual Ibsen Centre
https://www.hf.uio.no/is/english/services/virtual-ibsen-centre/on-ibsen-s-life/biography/
This website offers a treasure trove of resources related to Henrik Ibsen, his life, his works, and his inestimable impact on the world of the theatre.
