1. Append **g**\ *lon*/*lat* for :ref:`map coordinates <Reference_Points_g>`. Requires both |-R| and |-J| to be set.
2. Append **j**\ *code* or **J**\ *code* for setting the *refpoint* via a 2-char
   :ref:`justification code <Reference_Points_j>` that refers to the (invisible) projected map bounding box. Requires
   both |-R| and |-J| to be set.
3. Append **n**\ *xn*/*yn* for :ref:`normalized bounding box coordinates <Reference_Points_n>` (0-1). Requires both
   |-R| and |-J| to be set.
4. Append **x**\ *x*/*y* for :ref:`plot coordinates <Reference_Points_x>` (append **c**\ m, **i**\ nch, or
   **p**\ point).