diff --git a/chapter-11.md b/chapter-11.md
index 0bb064f..0543d00 100644
--- a/chapter-11.md
+++ b/chapter-11.md
@@ -195,7 +195,7 @@ to the memory architectures, the 8-bit bus cycle-eater is replaced by a
 new form of the wait state cycle-eater: wait states on accesses to
 normal system memory.
 
-#### System Wait States {#Heading6 align="center"}
+#### System Wait States
 
 The 286 and 386 were designed to lose relatively little performance to
 the prefetch queue cycle-eater...*when used with zero-wait-state
@@ -342,7 +342,7 @@ Of course, those are exactly the rules that apply to 8088 optimization
 as well. Isn't it convenient that the same general rules apply across
 the board?
 
-#### Data Alignment {#Heading7 align="center"}
+#### Data Alignment
 
 Thanks to its 16-bit bus, the 286 can access word-sized memory variables
 just as fast as byte-sized variables. There's a catch, however: That's
@@ -534,7 +534,7 @@ that consistently provides a reasonable return for bytes and effort
 expended, although sometimes it also pays to word-align tight
 time-critical loops.
 
-#### Alignment and the 386 {#Heading9 align="center"}
+#### Alignment and the 386
 
 So far we've only discussed alignment as it pertains to the 286. What,
 you may well ask, of the 386?
@@ -555,7 +555,7 @@ performance would dictate doubleword alignment of subroutines, that
 takes 3 bytes, a high price to pay for an optimization that improves
 performance *only* on the post 286 processors.
 
-#### Alignment and the Stack {#Heading10 align="center"}
+#### Alignment and the Stack
 
 One side-effect of the data alignment cycle-eater of the 286 and 386 is
 that you should *never* allow the stack pointer to become odd. (You can
@@ -580,7 +580,7 @@ slowly than it normally would. The same goes for decrementing twice; use
 > ![](images/i.jpg)
 > Keep the stack pointer aligned at all times.
 
-#### The DRAM Refresh Cycle-Eater: Still an Act of God {#Heading11 align="center"}
+#### The DRAM Refresh Cycle-Eater: Still an Act of God
 
 The DRAM refresh cycle-eater is the cycle-eater that's least changed
 from its 8088 form on the 286 and 386. In the AT, DRAM refresh uses a
@@ -606,7 +606,7 @@ an act of God, and there's not a blessed thing you can do about it.
 Happily, the internal caches of the 486 and Pentium make DRAM refresh
 largely a performance non-issue on those processors.
 
-#### The Display Adapter Cycle-Eater {#Heading12 align="center"}
+#### The Display Adapter Cycle-Eater
 
 Finally we come to the last of the cycle-eaters, the display adapter
 cycle-eater. There are two ways of looking at this cycle-eater on
@@ -782,7 +782,7 @@ unless you play some unorthodox tricks with the segment registers.
 > as Windows, so I'd recommend against using them. If you want 4-gigabyte
 > segments, use a 32-bit environment such as Win32.
 
-#### Optimization Rules: The More Things Change... {#Heading15 align="center"}
+#### Optimization Rules: The More Things Change...
 
 Let's see what we've learned about 286/386 optimization. Mostly what
 we've learned is that our familiar PC cycle-eaters still apply, although
@@ -805,7 +805,7 @@ that's the data alignment cycle-eater. From the data alignment
 cycle-eater we get a new rule: Word-align your word-sized variables, and
 start your subroutines at even addresses.
 
-#### Detailed Optimization {#Heading16 align="center"}
+#### Detailed Optimization
 
 While the major 8088 optimization rules hold true on computers built
 around the 286 and 386, many of the instruction-specific optimizations
diff --git a/chapter-44.md b/chapter-44.md
index f8f11a4..164f567 100644
--- a/chapter-44.md
+++ b/chapter-44.md
@@ -712,7 +712,7 @@ at the maximum possible rate of once per frame even on a 1985-vintage
 8-MHz AT. In this case, faster performance would result only in a longer
 wait for the page to flip.
 
-#### Write Mode 3 {#Heading5 align="center"}
+#### Write Mode 3
 
 It's possible to update the bitmap very efficiently on the VGA, because
 the VGA can draw up to 8 pixels at once, and because the VGA provides a
@@ -819,7 +819,7 @@ coincidentally, the sample application draws only single-color objects
 within the animation area; this allows write mode 3 to be used for all
 drawing, in keeping with our desire for speedy screen updates.
 
-#### Drawing Text {#Heading6 align="center"}
+#### Drawing Text
 
 We'll need text in the sample application; is that also a good use for
 write mode 3? Sometimes it is, but not in this particular case.
@@ -870,7 +870,7 @@ are 10 ways to do it, each with unique strengths and weaknesses. Your
 mission, should you decide to accept it, is to figure out which one is
 best for your particular application.
 
-#### Page Flipping {#Heading7 align="center"}
+#### Page Flipping
 
 Now that we know how to update the screen reasonably quickly, it's time
 to get on to the fun stuff. Page flipping answers the second requirement
@@ -913,7 +913,7 @@ so on *ad infinitum.*
 
 ![**Figure 44.1**  *Memory allocation for mode 10h page flipping.*](images/44-01.jpg)
 
-#### Knowing When to Flip {#Heading8 align="center"}
+#### Knowing When to Flip
 
 There's a hitch, though, and that hitch is knowing exactly when it is
 that the page has flipped. The page doesn't flip the instant that you
diff --git a/chapter-46.md b/chapter-46.md
index ff2bc9e..4e5f0a9 100644
--- a/chapter-46.md
+++ b/chapter-46.md
@@ -671,7 +671,7 @@ logic to produce more interesting and less predictable
 internal-animation effects, such as jumping, ducking, running, and the
 like.
 
-#### Dirty-Rectangle Management {#Heading6 align="center"}
+#### Dirty-Rectangle Management
 
 As mentioned above, dirty-rectangle animation makes it possible to
 access display memory a minimum number of times. The previous chapter's
diff --git a/chapter-54.md b/chapter-54.md
index 01b93f6..1fb0579 100644
--- a/chapter-54.md
+++ b/chapter-54.md
@@ -965,7 +965,7 @@ There are other sorts of shading components, including transparency and
 atmospheric effects, but the ambient and diffuse-shading components are
 all we're going to deal with in X-Sharp.
 
-#### Ambient Shading {#Heading5 align="center"}
+#### Ambient Shading
 
 The basic model for both ambient and diffuse shading is a simple one.
 Each surface has a reflectivity between 0 and 1, where 0 means all light
@@ -988,7 +988,7 @@ available palette of colors; I'll do that in the next chapter. Ambient
 shading isn't the whole shading picture, though. In fact, scenes tend to
 look pretty bland without diffuse shading.
 
-#### Diffuse Shading {#Heading6 align="center"}
+#### Diffuse Shading
 
 Diffuse shading is more complicated than ambient shading, because the
 effective intensity of directed light falling on a surface depends on
diff --git a/chapter-57.md b/chapter-57.md
index 074f387..5e1ec87 100644
--- a/chapter-57.md
+++ b/chapter-57.md
@@ -265,7 +265,7 @@ even human figures). Just map the desired texture onto the underlying
 polygonal framework of an object, and let double-DDA texture mapping do
 the rest.
 
-#### Fast Texture Mapping {#Heading7 align="center"}
+#### Fast Texture Mapping
 
 Of course, there's a problem with mapping a texture across many
 polygons: Texture mapping is slow. If you run DEMO1 and move the ball up