Cleaning up DataSource Warnings in my app

I am trying to fix the following warning when loading a DataSource:

=== 2015-06-18 10:42:29,655 - r [7-26] WARN com.isomorphic.validation.Validation:374 - Element is an instance of type ComboBoxItem, which does not inherit from declared field type DataSourceField at /DataSource[@ID=triad_cborg2000_common_locationsSearchDS]/fields/6

for this field constructor="ComboBoxItem" but I do not know what to set the type attribute.

Please let me know.

Also, I remember finding a document that outlined all of the type attributes choices for fields for the DataSource xml file.

Please let me know where that document is as I cannot find it.