optional, single

ref=identifier of the lens to be cross-referenced

Via <lensref ref="id_of_lens_to_be_cross-referenced"/> access to data stored under this identifier is possible. By means of this it is possible to exactly list the equipment configuration used during a specific dive, for example.

<dive>

—

<dive>

<uddf version="2.2.0">
    <generator>
        <!-- information about the generating software -->
    </generator>
    <diver>
        <owner id="o1">
            <!-- description of the owner of the UDDF file -->
            <equipment>
                <lens id="my_lens">
                    <!-- description of the lens used -->
                </lens>
                <!-- description of more equipment used by the owner of the UDDF file -->
            </equipment>
        </owner>
        <buddy id="b1">
            <!-- description of a dive buddy -->
        </buddy>
        <!-- here can stand more <buddy> elements, if necessary -->
    </diver>
    <!-- here can stand more sections -->
    <profiledata>
        <repetitiongroup>
            <dive id="dive-1">
                <!-- description of the first dive -->
                <!-- description of (cross-referencing on) equipment used -->
                <!-- lens: -->
                <lensref ref="my_lens"/>
                <!-- here cross-referencing on further equipment is possible -->
            </dive>
            <!-- here description of further dives -->
        </repetitiongroup>
        <!-- here can stand more <repetitiongroup> elements -->
    </profiledata>
</uddf>