Perhaps you should try some spelling variations:
"a robert j. hellman book" » "a robert j. hellman joel", "gal robert j. hellman book", "a robert _. hellman book", "a robert e. hellman book"
"a robust b. heitmann book" » "a robust _. heitmann book", "a robert b. heitmann book", "a robust b. heimann book", "a robust b. heinemann book", "a robust b. hermann book"
"_ robust b. heilman book" » "_ robust _. heilman book", "_ robert b. heilman book", "_ robust b. heilmann book"

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