“…Among the reviewed works several of them use some form of RNNs. classical RNNs [86 ], long short‐term memory (LSTM) [16, 67, 69, 70, 73, 76, 83 ], contextual long short‐term memory (CLSTM) [72 ], bidirectional recurrent neural networks (BRNNs) [17, 74 ], bidirectional gated recurrent unit (BGRU) [83 ], and bidirectional long short‐term memory (BLSTM) [14, 15, 19, 77, 79, 82–85 ].…”