One day during a school vacation, some Baha'i students who were attending school in Beirut were visiting Haifa. One of them had a geography book. Abdu'l-Baha looked at it and asked if He could keep it, and the student gladly consented. Abdu'l-Baha based the list of countries in the Tablets of the Divine Plan, and the regions of the United States to which He addressed several of those Tablets, on the contents that book. That geography book is now in the US National Archives. Here is a copy of its cover, and of one of the maps in it.
(Both images copyright © 2011 Baha'i National Archives, Wilmette, used with permission)