這位選擇權老手以前出過一本書: the option advisor，英文版我有買，還在在書架上，大約放了10年了。
在本書的第216頁這樣寫:
there are numerous options-selling strategies. With
covered writing strategies you write calls against stock you own. We don't discusss covered call writing strategies here, as abundant literature is available on the subject elsewhere. Instead, let us focus on profitable approaches with which you may be less familiar.
Uncovered equity put selling, for example, can be an excellent approach to generate income or acquiring quality stock at lower prices; we will disucss put selling later in this chapter. In addition, you may not be aware of another powerful strategy that can generate 15 percent to 20 percent returns in one month or less, with winning trades achievable more than 90 percent of the time if you are a
good market timer(前提). This strategy is known as
credit spread investing.
他的官網:
http://www.schaeffersresearch.com/
基本上，作者是比較偏好買選擇權的人，不過他書中也有寫到一些賣方策略。
在本書的218頁上方，作者對credit cpread做了一個大家都了解的簡單定義:
A credit spread involves two options: an out-of-the-money options that you write(sell) and a furhter out-of-the-money option you buy as a hedge. Both the option sale and the option purchase are opened simultaneously, at a net credit to your account for the spread.