(新闻稿). Honolulu, Hawaii: Blue Planet Foundation. 10 June 2015 [8 June 2019]. (原始内容存档于2023-04-08). About Blue Startups. Blue Startups. [2023-02-17]. (原始内容存档于2023-05-06)
Building)和避暑別墅格雷克利夫(英语:Graycliff)。 Blue Sky Mausoleum of Frank Lloyd Wright: Designed 1928, Built 2004. Forest Lawn Heritage Foundation. 2005 [2022-01-30]. ISBN 978-0-9652756-3-7
LABEL(OPENPLAQUES)(使用情况) Blue plaque section of English Heritage's site (页面存档备份,存于互联网档案馆) Blue plaques of The Heritage Foundation Community-based project