"internal mistake" is correct and can be used in written English.
It is typically used to refer to an error or mistake made by someone within an organization. For example, "We apologize for the internal mistake that caused your order to be delayed."
In the interview, Mr. Dahlan acknowledged "internal mistakes" by the Palestinian leadership, but warned that removing Mr. Arafat would result only in a more extreme Palestinian leadership.
But unlike the error at Google, which the company blamed on an outside filing agent, R.R. Donnelley & Sons, the situations at Dow and Daimler appear to be a result of internal mistakes.
-- things started changing and youth in Arab countries would mock those who still believe in conspiracy theories and would instead speculate about the internal mistakes that could have possibly led to the situation at hand.
A Nigerian student, Umar Farouk Abdulmuttalab, forever known as the underwear bomber, tried to ignite himself on an airplane on Christmas Day after, staggeringly, getting past security despite having been previously flagged (an unacceptable internal administrative mistake, revealing a lack of communication between security agencies).
Allegheny's problems are largely the result of internal accounting mistakes, investor skepticism over the short-term prospects of the electricity industry and a disastrous effort to enter the energy-trading business through the purchase and subsequent sale of trading operations from Merrill Lynch.
A high-density cell culture or one subject to perturbation may require less smoothing to ensure that rapid physiological changes are not mistaken for internal standard error.
In court filings RDR argues that Mr. Vander Ark's book "provides a significant amount of original analysis and commentary concerning everything from insights into the personality of key characters, relationships among them, the meaning of various historical and literary allusions, as well as internal inconsistencies and mistakes in the novels".
Companies do these days talk a lot about creating an internal culture where mistakes are part of the learning process and therefore should be shared, but have not generally reached the stage that this also needs to extend to their relationships to external stakeholders.
The chief financial officer at Apollo Group, the for-profit education company, resigned after an internal probe revealed mistakes in stock option accounting.
Both external and internal realities are mistaken to the degree that we see them as "two" and not "nondual" constructions arising out of a single mental stream.
