In 19.171 draw:formula we have the specification function_reference::= "?" name name::= [^#x20#x9]+ So when parsing a function_reference is terminated by the first space or tab character (or string end). On the other hand LO writes file content such as: <draw:equation draw:name="f31" draw:formula="sqrt(((?f29-?f24)*(?f29-?f24))+((?f28-?f23)*(?f28-?f23)))"/> Note that my interpretation of 19.171 would indicate that "f29-?f24)*(?f29-?f24))+((?f28-?f23)*(?f28-?f23)))" is a function reference name. I ti pretty clear that that is not what is thought. More likely the first function reference is either f29 or f2 since the otehr names were not defined in this case. Is my interpretation of section 19.171 correct? Andreas -- Andreas J. Guelzow, PhD, FTICA Concordia University College of Alberta Attachment: signature.asc Description: This is a digitally signed message part