[1] [CITE[Greenwich Time: And the Discovery of the Longitude - Derek Howse - Google ブックス]]
([TIME[2017-06-20 19:22:30 +09:00]])
<https://books.google.co.jp/books/about/Greenwich_Time.html?id=YOzaAAAAMAAJ&redir_esc=y>

[2] [CITE@en[Greenwich Time : Derek Howse : Free Download & Streaming : Internet Archive]]
([TIME[2017-06-20 19:23:49 +09:00]])
<https://archive.org/details/GreenwichTime>