Answer:
The errors are:
1. When the author is quoted in a sentence, his name is not in brackets, only the year of his book. For example, the write-up should have read like this: "Shindell (2008) argues that hackers increasingly integrate ..." This is a more appropriate way of citing an author. However, the writer could do well to show the exact words of Shindell with quotation marks to differentiate from his or her words.
2. Two sentences were put in quotation marks without any indication of the author(s) to which the words were attributed. Since they look like direct quotes from Shindell, the write-up should read like this: Shindell (2008) said, "during an attack, victims ..." And the second quoted sentence should read like this: "... were hit with ransomware in the previous 12 months," according to Shindell (2008).
Explanation:
Referencing somebody else's intellectual property helps to avoid plagiarism, which is considered as a very serious crime.