At least one of the one or more sources of {TAIL ~ a sanitizing agent} may be {HEAD ~ a source} of germicidal ultraviolet light 
At least one of the one or more sources of { TAIL ~ a sanitizing agent } may be { HEAD ~ a source } of germicidal ultraviolet light
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH