+ /**
+ * Write the given {@link Contact} in the {@link Appendable}.
+ *
+ * @param writer
+ * the {@link Appendable}
+ * @param contact
+ * the {@link Contact} to write
+ * @param startingBKey
+ * the starting BKey number (all the other will follow) or -1 for
+ * no BKey
+ * @param format
+ * the {@link Format} to export to
+ *
+ * @throws IOException
+ * in case of IO error
+ */
+ public static void write(Appendable writer, Contact contact, Format format,
+ int startingBKey) throws IOException {