If you only have one appendix in a paper, label and refer to it as Appendix without a letter.
If you have more than one appendix in a paper, refer to all appendices using a capital letter after “Appendix.” Alphabetize the appendices in the order you refer to them in the text (Appendix A, Appendix B, Appendix C, etc.).
Abbreviations and terminology must be consistent in all appendices in the same paper.
Formats and titles must be consistent.
Do not repeat the same data or information in different appendices.