Perhaps you should try some spelling variations:
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"a robert e. hellman book" » "a robert e. hellman joel", "a robert e. german book", "3 robert e. hellman book", "dr robert e. hellman book", "a robot e. hellman book", "a robert _. hellman book", "a robert j. hellman book"
"a robert e. heilmann book" » "3 robert e. heilmann book", "dr robert e. heilmann book", "a robot e. heilmann book", "a robert _. heilmann book", "a robert j. heilmann book", "a robert e. heilemann book", "a robert e. heimann book", "a robert e. heitmann book"

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