code: public LocalDate atDay(int dayOfQuarter) {
          ValueRange.of(1, lengthOfQuarter()).checkValidValue(dayOfQuarter, DAY_OF_QUARTER);
          boolean leap = Year.isLeap(year);
          Month month = quarter.firstMonth();
          while (dayOfQuarter > month.length(leap)) {
              dayOfQuarter -= month.length(leap);
              month = month.plus(1);
          }
          return LocalDate.of(year, month, dayOfQuarter);
      }
docs: Combines this year-quarter with a day-of-quarter to create a {@code LocalDate}.
  <p>
  This returns a {@code LocalDate} formed from this year-quarter and the specified day-of-quarter.
  <p>
  The day-of-quarter value must be valid for the year-quarter.
  <p>
  This method can be used as part of a chain to produce a date:
  <pre>
  LocalDate date = yearQuarter.atDay(day);
  </pre>
  
  @param dayOfQuarter  the day-of-quarter to use, from 1 to 92
  @return the date formed from this year-quarter and the specified day, not null
  @throws DateTimeException if the day is invalid for the year-quarter
  @see #isValidDay(int)