How many bird books were published by Neltje Blanchan in the 1900s?
5
1
2
1
2
1
3
2
1
3
2
1
3
2
1
3
2
1
4
3
2
1
4
3
2
1
4
3
2
1
4
3
2
1
5
4
3
2
1
5
4
3
2
1
5
4
0
3
2
1
5
4
3
2
0
1
5
4
3
2
1
0
5
4
3
2
1
5
4
0
3
2
1
5
4
3
2
0
1
5
4
3
2
6
1
0
5
4
3
2
6
5
4
0
3
7
6
5
4
3
7
0
6
5
4
7
6
0
5
4
7
6
5
4
0
7
6
5
4
8
7
0
6
5
8
7
6
0
5
8
7
6
5
0
8
7
6
9
5
8
7
6
9
11
8
7
6
9
11
8
7
6
10
9
11
8
7
6
10
9
11
8
7
6
12
10
9
11
8
7
6
12
13
10
9
11
8
7
6
12
13
10
9
11
8
7
6
12
13
10
9
11
8
7
14
6
12
13
123
66
112