You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is To make a positive identification with the help of a partial fingerprint, the points of similarity should be at least - and explain in detail?
For this different textbooks have given a different number:-

Parikh  → 16 characteristics
Reddy  →10 - 12 finer characteristics
Seth and Simpson → 16 - 20 characteristics

16 is given in more number of textbooks, so the answer is 16.