46. Geologists who practise within a partnership or joint-stock company must ensure that the fees and expenses relating to the professional services provided by geologists of the partnership or joint-stock company are always indicated separately on every invoice or statement of fees that the partnership or joint-stock company sends the client, except where a lump-sum payment has been agreed upon in writing with the client. Despite the foregoing, in the latter case, the statement or invoice must describe the professional services provided by geologists.