Podio Importer API - Multiple relationships?

While doing an import I'm wondering if there is a way to have the imported item reference multiple relationship fields.

For example, Branches app has three items with unique field values: 111, 222, 333.

Then the imported row has 111,222,333 as its column value (I've also tried semicolons instead of commas). Expected behavior would be to have the imported item relate to all three branches. Column mapping example in the import api payload:

            {
                field_id: FieldIds.Branch,
                value: {
                    'app_id': AppId.Branches,
                    'mappings': [
                        {
                            field_id: BranchFieldID.UID,
                            unique: true,
                            'value': {
                                column_id: '6' // sample value is like '111,222,333'
                            }
                        }
                    ]
                }
            },

Any clue if this is possible?

Never mind, their documentation has it all along. The trick is a semicolon with a line break