diff --git a/Makefile b/Makefile
index ea964bf769319cbaf9285b5353d840b275257cc6..19bab3daace84be5e84d9e7988a9977ddd9e9085 100644
--- a/Makefile
+++ b/Makefile
@@ -16,15 +16,11 @@ bib:
 
 # dessa forma somente os arquivos removidos são listados na saída
 clean:
-	@find . -xdev -iname \*~        -print -delete
-	@find . -xdev -iname \*.aux     -print -delete
-	@find . -xdev -name texput.log  -print -delete
-	@find . -xdev -name $(MAIN).log -print -delete
-	@find . -xdev -name $(MAIN).lot -print -delete
-	@find . -xdev -name $(MAIN).lof -print -delete
-	@find . -xdev -name $(MAIN).toc -print -delete
-	@find . -xdev -name $(MAIN).bbl -print -delete
-	@find . -xdev -name $(MAIN).blg -print -delete
+	@find . -xdev -iname \*~    -print -delete
+	@find . -xdev -iname \*.aux -print -delete
+	-rm -f texput.log
+	-rm -f $(MAIN).log $(MAIN).lot $(MAIN).lof
+	-rm -f $(MAIN).toc $(MAIN).bbl $(MAIN).blg
 
 purge: clean
 	@rm -f $(OUTPUT)
diff --git a/main.tex b/main.tex
index b5e98c27371bb7702d539e6291ae875f16f9d948..e7e7b0cbc5288883fd10e9640b81755440b662b8 100644
--- a/main.tex
+++ b/main.tex
@@ -121,10 +121,15 @@
 %=====================================================
 
 % Estilos de bibliografia recomendados (só descomentar um estilo!)
+% Mais infos: https://pt.sharelatex.com/learn/Bibtex_bibliography_styles
 \bibliographystyle{apalike-ptbr}	% [Maziero et al., 2006]
-%\bibliographystyle{plain}		% [1], [1, 2]
-%\bibliographystyle{alpha}		% [Maz06], ...
+%\bibliographystyle{alpha}		% [Maz06]
 %\bibliographystyle{plainnat}		% vide Google "LaTeX Natbib"
+%\bibliographystyle{plain}		% [1] ordem alfabética
+%\bibliographystyle{unsrt}		% [1] ordem de uso no texto
+
+% no estilo "unsrt", evita que citações nos índices sejam consideradas
+%\usepackage{notoccite}
 
 % base de bibliografia (BibTeX)
 \bibliography{referencias}
diff --git a/main_maziero.pdf b/main_maziero.pdf
index 6574b53525aaedbc04293abc57854054be02e8dc..f4da99eabbd76015e4ff84b9c13729a72318b0ea 100644
Binary files a/main_maziero.pdf and b/main_maziero.pdf differ
diff --git a/ppginf.cls b/ppginf.cls
index 58cff7b56fd6e92f2414e69d7b5dddc578a5b959..05020617d0ab2b731bb3888d5c36bf5f0ce84b6e 100644
--- a/ppginf.cls
+++ b/ppginf.cls
@@ -160,6 +160,7 @@
 
 % Contra todas as normas tipográficas, a biblioteca da UFPR exige que a numeração
 % da introdução leve em conta as páginas preliminares (ou seja, não comece em 1).
+% Caso as regras de sua universidade sejam "normais", comente as linhas abaixo.
 \renewcommand\pagenumbering[1]{%
   %\global\c@page\@ne % this resets the counter
   \gdef\thepage{\csname @#1\endcsname\c@page}%