I'm new to DITA but familiar with structured Frame. I'm trying to open, edit and rebrand a large amount of legacy DITA content generated from IBM over the past many years. I'm unable to open the files in Frame 16.0.1--I get an error message in the console that the cause is the dtd--all of the files (so far as I can tell inspecting in notepad) use non-OASIS standard dtds, such as these: <!DOCTYPE reference PUBLIC "-//IBM//DTD DITA IBM Reference//EN" "ibm-reference.dtd">
<!DOCTYPE concept PUBLIC "-//IBM//DTD DITA IBM Concept//EN"
<!DOCTYPE task PUBLIC "-//IBM//DTD DITA IBM Task//EN"
<!DOCTYPE map PUBLIC "-//IBM//DTD DITA IBM Map//EN"
Does anyone know where I can get these dtds? They don't seem to be provided with any of the source files I received. I experimented with replacing one of the ibm-task.dtd with an OASIS standard task.dtd, and FM opened the file without issue...