49ers Patrick Willis retiring after injury-shortened season – The Denver Post
49ers Alumnus Patrick Willis to Be Inducted into Bay Area Sports Hall of Fame
49ers' Patrick Willis retires 'happy' – The Mercury News
Patrick Willis, retired San Francisco 49ers all-Pro linebacker, guest speaker at Jackson-Madison County Sports Hall of Fame - WNWS Radio - Jackson, Tennessee, USA
Season over for 49ers LB Patrick Willis
San Francisco linebacker Patrick Willis announces his retirement - The Globe and Mail
Patrick Willis working full-time at tech startup in Silicon Valley
Patrick Willis still thriving after early 49ers retirement
Bleacher Report - San Francisco 49ers make it official: Patrick Willis will retire. Details