[R] Error message when using "revtools" package

[John]

Hi,

    I tried to read a bib file by  "read_bibliography" function in
"revtools" package, but I got an error message but don't know how to fix
it. Anyone can help? Thank you so much!!

###
   library(revtools)
   data2 <- read_bibliography("mlf_ref201105_2.bib", return_df = FALSE)
###

Error message:
####
Error in if (any(names(entry_list) == "author")) { :
  missing value where TRUE/FALSE needed
####

   My "mlf_ref201105_2.bib" file is attached.

   I have no problem reading the built-in ris file:

####
file_location <- system.file(
  "extdata",
  "avian_ecology_bibliography.ris",
  package = "revtools")
x <- read_bibliography(file_location)
####