search documents that do not match a specific type

[robobot]

Hello there,
i have space called "Incoming Invoices" with 1000 documents in it. the documents have a custom type "invoice". Now near 100 documents do not have that content type, they just have the standard content assigned. Now i must find these documents. how will the lucene query look like ? i know how to search for specific documents according to the nice tutorial
http://ecmarchitect.com/images/articles/alfresco-content/content-article.pdf
but how can i retrieve all documents that have the standard type assigned ?
Thank you.
Steve

[robobot]

another try. how can i build the lucene query to match a field that has no value ?

i tried the following:

+@invoice\\:invoiceId:null
+@invoice\\:invoiceId:
+@invoice\\:invoiceId: ''

nothing worked. :?:

[robobot]

thank god, he helped me figuring out that stuff: this query will bring me a happy day:

+PATH:"/app:company_home/app:user_homes/cm:MyWorkspace/cm:Invoices/*"-TYPE:"{invoice.model}IncomingInvoices"