Some FGDC are not valid (containing non-valid elements metadata/method).
See: Richard Cooke-> Archaeological Investigations in Panama-> Field investigations (1969-2010)-> Cerro Juan Diaz
Then see Looter pits/Operation 1/ Operation 2/…/Operation 8, these xml files are not valid. These data were created by form FGDC-CTPlot (si-islandora), which contain invalid xml elements <metadata><method>. We have fixed the form on si-researchersdev, but the Archaelogy team had used the wrong form to upload data.

Update: 11/21/2013
Some EACCPF projects are not valid xml too. Need to fix the data.