http://www.fee.org/library/detail/i-pencil-audio-pdf-and-html http://www.fee.org/library/detail/i-pencil-audio-pdf-and-htm... is the 50th anniversary edition wi

http://www.fee.org/library/detail/i-pencil-audio-pdf-and-html http://www.fee.org/library/detail/i-pencil-audio-pdf-and-htm... is the 50th anniversary edition with foreword and afterword, and audio and PDF versions.