invoke task, report template with servlet odata, change criteria

Hi all, 

   i've tried to call this servlet

POST /Windchill/servlet/odata/IE/InvokeIETask

with this body

{ 
 "Task": "com/ptc/windchill/enterprise/report/ExecuteReportTemplate.xml",
 "Params": [
 {
 "Name": "object_ref",
 "Value": "wt.query.template.ReportTemplate:6852467828"
 }}
 ]
}

now I need to change the report criteria directly from the API. I tried to add a parameter but it doesn't seem to work.

For example (but it doesn't works)

{ 
 "Task": "com/ptc/windchill/enterprise/report/ExecuteReportTemplate.xml",
 "Params": [
 {
 "Name": "object_ref",
 "Value": "wt.query.template.ReportTemplate:6852467828"
 },
 {
 "Name":"where",
 "Value":"((Associated Part.Latest Iteration equals 1) AND (Part Master.Number in 1234))"
 }
 ]
}

Where can I find documentation? what is the correct parameter?