R. W. Chambers 
Beowulf: An Introduction to the Study of the Poem with a Discussion of the Stories of Offa and Finn [EPUB ebook] 

After nearly a hundred years, this book is still one of the most comprehensive studies of the epic poem 'Beowulf.’ The author of this book, Wilson Chambers, gives a detailed explanation of the poem and provides a reader with an interesting backstory about the main characters.