regex optional whitespace characters
// Add a s? if a space can be allowed.
// s stands for white space
// ? says the preceding character may occur once or not occur.
// If more than one spaces are allowed and is optional, use s*.
// * says preceding character can occur zero or more times.
'#<a hrefs?="(.*?)" titles?="(.*?)"><img alts?="(.*?)" srcs?="(.*?)"[s*]widths?="150"[s*]heights?="(.*?)"></a>#'