http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
volumes : illustrations, diagram ; 23 cm.
[4] 4th year -- [5] 5th year -- [6] 6th year.
These books cover works for a year in nature study and health eucation for the 4th, 5th and 6th- grades