fix appendices

03-results-01.Rmd

-# Results {#results-1}
+# First Results {#results-1}
 
 First results chapter.
 

04-results-02.Rmd

-# Results {#results-2}
+# Second Results {#results-2}
 
 Second results chapter. Here's a reference: [@abe2009].
 

appendix.Rmd → 20-appendix.Rmd

 # (APPENDIX) Appendix {-}
+<!-- Add Appendix to TOC -->
 \addappheadtotoc
+<!-- Appendix cover page -->
+\appendixpage  
+\cleardoublepage
 

_bookdown.yml

 book_filename: "thesis-dissertaion" # Change this to the actual title
 delete_merged_file: true
-rmd_files: ["index.Rmd","00-preface.Rmd", "01-intro.Rmd","02-methods.Rmd", "03-results-01.Rmd", "04-results-02.Rmd","05-discussion.Rmd", "appendix.Rmd","20-appendix-a.Rmd","21-appendix-b.Rmd", "99-references.Rmd"]
+rmd_files: ["index.Rmd","00-preface.Rmd", "01-intro.Rmd","02-methods.Rmd", "03-results-01.Rmd", "04-results-02.Rmd","05-discussion.Rmd", "20-appendix.Rmd","21-appendix-a.Rmd","22-appendix-b.Rmd", "99-references.Rmd"]
 language:
   ui:
     chapter_name: "Chapter "
\ No newline at end of file