[NTG-context] error: Control sequence expected instead of undefined

Hi, I got an error message as following: Control sequence expected instead of undefined If I comment out the “\externalfigure[][]” line, then there is no error message. I don’t know what is wrong in the sample code. Please check the code. Thank you for reading. Best regards, Dalyoung %%%********************* \starttext \in{figure}[fig:kruskal1] is my point. \startplacefigure[location=,reference=fig:kruskal1,title={}] \externalfigure[cow][width=.5\makeupwidth] \stopplacefigure \stoptext %%%%%