Renamed docID attribute to refID in the modificationRecord so the attribute name is consistent; the docID attribute is deprecated but remains in place for compatibility with older documents.

Added correlatesWith and correlation sub-elements of uncertainty element to allow for multiple-dimensioned linear correlation of uncertainty of selected functions and variables.

Added a new element, contactInfo, to replace the single address element. This format supports multiple ways to indicate how to contact the author of a document or reference. address is deprecated but is retained for backwards compatibility. This element also replaces the email and xns attributes of author.

Fixed a typographical error in ungriddedTableRef element: incorrect gtID attribute corrected to utID.

Allowed multiple author elements wherever only one had been allowed before.

Added a new tag, isStdAIAA , to indicate that a variableDef refers to one of the standard AIAA variables.

Removed [un]griddedTable[Ref|Def] sub-elements of the confidenceBound element since this leads to circular logic.

Changed SYSTEM ID to reflect new daveml.nasa.gov domain availability.

Removed true email from examples to protect privacy of individual contributors.

Added a new attribute, interpolate, to the independentVarPts element to indicate whether the table interpolation should be linear or cubic spline in the given dimension [modified to include quadratic in version 1.9].

Added a new tag, isState, to indicate that a variableDef refers to a state variable in the model.

Added a new tag, isStateDeriv, to indicate that a variableDef refers to a state derivative variable in the model.