api_key = get_api_key(NULL, error = FALSE)
if (!is.null(api_key)){
x = article_retrieval("S1053811915002700", identifier = "pii")
} else {
x = article_retrieval("S1053811915002700",
identifier = "pii",
api_key_error = FALSE)
}
Run the code above in your browser using DataLab