I get asked all the time for my favourite resources on the value of Agile practices to organisations. Here are the ones that I use most often in my courses -- a mix of articles and videos.
The New New Product Development Game, Harvard Business Review, January 1986
Inspiration for creation of the Scrum Framework. Well worth a read, to bring life to the original values and objectives of Scrum.
The Path to Agility (video), part 1, Ken Schwaber, 2010
Ken's anecdotes about the challenges faced by teams moving to iterative and incremental approaches are as relevant today as they were when he gave this presentation in 2010.
Embracing Agile, Harvard Business Review, May 2016
To me this is a follow-up to the 1986 article 'The New New Product Development Game', co-written by one of that article's authors, and Jeff Sutherland.
Scrum Guide updates (video), Ken Schwaber and Jeff Sutherland, July 2016
Recorded webinar with the Scrum founders on the first update to the Scrum guide since 2013 -- the important addition of the 5 Scrum Values.