bibliography entry in Rmd document is not code (#1175)

src/jupytext/cell_reader.py

@@ -443,7 +443,9 @@ def find_cell_end(self, lines):
                         return i - 1, i, False
                     return i, i, False
 
-                if self.start_code_re.match(line):
+                if self.start_code_re.match(line) and not line.startswith(
+                    "```{bibliography}"
+                ):
                     # Cells with a .noeval attribute are markdown cells #347
                     _, metadata = self.options_to_metadata(
                         self.start_code_re.findall(line)[0]

tests/functional/simple_notebooks/test_read_simple_rmd.py

@@ -264,3 +264,20 @@ def test_commented_triple_quote_1060(line):
     compare(rmd2, rmd)
     nb2 = jupytext.reads(rmd, fmt="Rmd")
     compare_notebooks(nb2, nb)
+
+
+def test_bibliography_in_rmd(
+    rmd="""Issue #1161
+
+The bibliography section below should not
+become a code cell
+
+```{bibliography}
+```
+""",
+):
+    nb = jupytext.reads(rmd, fmt="Rmd")
+    assert len(nb.cells) == 1, nb.cells
+    assert nb.cells[0].cell_type == "markdown"
+    rmd2 = jupytext.writes(nb, fmt="Rmd")
+    compare(rmd2, rmd)