diff --git a/4_dados_gtfs.en.qmd b/4_dados_gtfs.en.qmd
index c459797..5579588 100644
--- a/4_dados_gtfs.en.qmd
+++ b/4_dados_gtfs.en.qmd
@@ -137,6 +137,7 @@ File used to describe the different service calendars in a public transport syst
 #| echo: false
 #| label: tbl-calendar
 #| tbl-cap: "`calendar.txt` example. Source: SPTrans"
+#| output: "asis"
 gtfs$calendar[
   ,
   `:=`(
@@ -145,6 +146,8 @@ gtfs$calendar[
   )
 ]
 
+gtfs$calendar[, service_id := gsub("\\_", "\\\\_", service_id)]
+
 knitr::kable(gtfs$calendar)
 ```