zeba Annals of American History (Encyclopædia Britannica)
zebo Britannica Academic (formally Encyclopædia Britannica Online)
zelz Britannica Fundamentals
zepl Britannica Library
zeja Britannica Online Japan
zebk Britannica School Elementary
zehs Britannica School High
zebm Britannica School Middle
zbds:usg EBSCO Discovery Service (Scholar View)
zemd Enciclopedia Moderna
zeun Encyclopædia Universalis
zeju Encyclopædia Universalis Junior
zeeo Escolar Online (from Encyclopædia Britannica)
zeiq Image Quest (Britannica)
zebd Merriam-Webster's Collegiate Dictionary (in Encyclopædia Britannica Online)
zeos Original Sources