CSS - 如何删除锚定图像之间的空白

我有两个互相重叠的锚定图像，用换行符分隔。我希望图像直接坐在彼此的顶部，但在Firefox中，图像之间存在差距。它适用于IE7。我能够解决这个问题的唯一方法是改变行高（我不想这么做）。

I have two anchored images on top of each other, separated with a line break. I want the images to sit directly on top of each other, but in Firefox there is a gap between the images. It works in IE7. The only way I have been able to fix this is by changing the line-height (which I don't want to do).

<a href="image.jpg">
    <img height="75" width="75" src="image.jpg" />
</a>
<br/>
<a href="image2.jpg">
    <img height="75" width="75" src="image2.jpg" />
</a>